Reject case-varied LSPS5 replay signatures - #4701

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tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
Merged

Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

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LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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@joostjager@ldk-reviews-bot@ldk-claude-review-bot@TheBlueMatt@tnull
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Reject case-varied LSPS5 replay signatures - #4701

Merged
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
Merged

Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

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@joostjager

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LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
1 check passed
@TheBlueMatt

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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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@joostjager@ldk-reviews-bot@ldk-claude-review-bot@TheBlueMatt@tnull
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Reject case-varied LSPS5 replay signatures - #4701

Merged
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
Merged

Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

Conversation

@joostjager

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Contributor

LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
@ldk-reviews-bot

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👋 Hi! Please choose at least one reviewer by assigning them on the right bar.
If no reviewers are assigned within 10 minutes, I'll automatically assign one.
Once the first reviewer has submitted a review, a second will be assigned if required.

@ldk-claude-review-bot

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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
1 check passed
@TheBlueMatt

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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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@joostjager@ldk-reviews-bot@ldk-claude-review-bot@TheBlueMatt@tnull
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
Skip to content

Reject case-varied LSPS5 replay signatures - #4701

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tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
Merged

Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

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@joostjager

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LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
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👋 Hi! Please choose at least one reviewer by assigning them on the right bar.
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Once the first reviewer has submitted a review, a second will be assigned if required.

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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
1 check passed
@TheBlueMatt

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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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@joostjager@ldk-reviews-bot@ldk-claude-review-bot@TheBlueMatt@tnull
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '
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Reject case-varied LSPS5 replay signatures - #4701

Merged
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
Merged

Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

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@joostjager

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LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
@ldk-reviews-bot

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👋 Hi! Please choose at least one reviewer by assigning them on the right bar.
If no reviewers are assigned within 10 minutes, I'll automatically assign one.
Once the first reviewer has submitted a review, a second will be assigned if required.

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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
1 check passed
@TheBlueMatt

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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Reject case-varied LSPS5 replay signatures - #4701

Merged
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
Merged

Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

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@joostjager

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LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
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@TheBlueMatt

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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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@joostjager@ldk-reviews-bot@ldk-claude-review-bot@TheBlueMatt@tnull
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Reject case-varied LSPS5 replay signatures - #4701

Merged
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
Merged

Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

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@joostjager

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LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
1 check passed
@TheBlueMatt

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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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5 participants

@joostjager@ldk-reviews-bot@ldk-claude-review-bot@TheBlueMatt@tnull
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();
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Reject case-varied LSPS5 replay signatures - #4701

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tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay
Jun 16, 2026
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Reject case-varied LSPS5 replay signatures#4701
tnull merged 1 commit into
lightningdevkit:mainfrom
joostjager:fix-lsps5-case-replay

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@joostjager

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LSPS5 webhook signatures are zbase32 strings, and the verifier accepts case aliases when decoding them. The replay cache compared raw header strings, so a case-only change could bypass immediate replay detection even though it represented the same signature bytes.

Canonicalize the verified signature text before cache lookup and storage. Keying the replay cache on decoded signature bytes would be the semantic ideal, but doing that locally would decode once in the validator and again inside message_signing::verify. This keeps the fix local while matching the verifier's identity semantics. Add regression coverage for the case-varied replay.

LSPS5 webhook signatures are zbase32 strings, and the verifier
accepts case aliases when decoding them. The replay cache compared
raw header strings, so a case-only change could bypass immediate
replay detection even though it represented the same signature bytes.
Canonicalize the verified signature text before cache lookup and
storage. Keying the replay cache on decoded signature bytes would be
the semantic ideal, but doing that locally would decode once in the
validator and again inside message_signing::verify. This keeps the
fix local while matching the verifier's identity semantics. Add
regression coverage for the case-varied replay.
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No issues found.

The fix correctly canonicalizes the signature to lowercase before the replay-cache lookup and storage, matching the verifier's case-insensitive zbase32 semantics:

  • base32.rs:140 decodes case-insensitively, and base32.rs:152-158 rejects non-zero trailing bits, so for a valid 65-byte sigrec (exactly 104 zbase32 chars, no padding slack), case is the only equivalence dimension. Lowercasing therefore fully captures the verifier's identity semantics without false collisions (the zbase32 alphabet has no lowercase collisions).
  • The regression test is valid: zbase32 signatures contain letters, so the uppercased variant differs from the original yet still verifies and is correctly detected as a replay.

@tnull
tnull merged commit c7fcdf6 into lightningdevkit:mainJun 16, 2026
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@TheBlueMatt

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Backported in #4706

@joostjagerjoostjager self-assigned this Jun 18, 2026
TheBlueMatt added a commit to TheBlueMatt/rust-lightning that referenced this pull request Jun 23, 2026
v0.2.3 - Jun 18, 2026 - "Through the Loupe"
API Updates
===========
* `DefaultMessageRouter` will now always generate blinded message paths that
provide no privacy (where our node is the introduction node) for nodes with
public channels. This works around an issue which will appear for any nodes
with LND peers that enable onion messaging - such peers will refuse to
forward BOLT 12 messages from unknown third parties, which most BOLT 12
payers rely on today (lightningdevkit#4647).
* Explicit `amount_msats` of 0 is rejected in BOLT 12 `Offer`s; `OfferBuilder`
now maps 0-amounts to an amount of `None` (lightningdevkit#4324).
Bug Fixes
=========
* `Features::supports_zero_conf` no longer clears the `ZeroConf` features and
`Features::requires_zero_conf` now correctly reports required, rather than
supported, status (lightningdevkit#4517).
* If an MPP payment is claimed but `ChannelMonitorUpdate`s for some parts are
still being completed asynchronously, further channel updates (e.g.
forwarding another payment) are pending and the node restarts, the channel
could have become stuck (lightningdevkit#4520).
* The presence of unconfirmed transactions actually no longer causes
`ElectrumSyncClient` to spuriously fail to sync (lightningdevkit#4590).
* LSPS1, LSPS2, and LSPS5 persistence will no longer get stuck and refuse to
persist again after a single failure from the KVStore (lightningdevkit#4597, lightningdevkit#4282).
* Dropping the future returned by
`OutputSweeper::regenerate_and_broadcast_spend_if_necessary` no longer
results in future calls to the same method being spuriously ignored (lightningdevkit#4598).
* Used async-receive offers are no longer refreshed on every timer tick once
their refresh time is reached (lightningdevkit#4672).
* `FilesystemStore::list_all_keys` will no longer fail if there are stale
intermediate files lying around from a previous unclean shutdown (lightningdevkit#4618).
* When forwarding an HTLC while in a blinded path with proportional fees over
200%, LDK will no longer spuriously allow a forward that pays us 1 msat too
little in fees (lightningdevkit#4697).
* Fixed a rare case where a channel could get stuck on reconnect when using
both async `ChannelMonitorUpdate` persistence and async signing (lightningdevkit#4684).
* If we had exactly zero balance in a zero-fee-commitment channel, the
counterparty was able to splice all of their balance out, violating the
reserve requirements they'd otherwise be forced to keep (lightningdevkit#4580).
* Providing an `Event::HTLCIntercepted` to the `LSPS2ServiceHandler` twice no
longer results in spuriously opening a channel early (lightningdevkit#4656).
* `Event::PaymentSent::fee_paid_msat` is no longer `None` in cases where
`ChannelManager::abandon_payment` was called before the payment ultimately
completes anyway (lightningdevkit#4651).
* `AnchorDescriptor::previous_utxo` now provides the correct `script_pubkey`
for non-zero-commitment-fee anchor channels (lightningdevkit#4669).
* Syncing a `ChainMonitor` using the `Confirm` trait will no longer write some
full `ChannelMonitor`s to disk several times per block (lightningdevkit#4544).
* `OMDomainResolver` now correctly accounts for failed queries when rate
limiting, ensuring we continue to respond to queries after failures (lightningdevkit#4591).
* Calling `ChannelManager::send_payment_with_route` without a `route_params`
and with an invalid `Route` will no longer panic (lightningdevkit#4707).
* `LSPS2ServiceHandler::channel_open_failed` now correctly fails intercepted
HTLCs rather than allowing them to fail just before expiry (lightningdevkit#4677).
* `StaticInvoice::is_offer_expired` was corrected to check offer, rather than
static invoice, expiry (lightningdevkit#4594).
* `lightning-custom-message`'s handling of `peer_connected` events now ensures
that sub-handlers will see a `peer_disconnected` event if a different
sub-handler refused the connection by `Err`ing `peer_connected` (lightningdevkit#4595).
* Replay protection for LSPS5 signatures now detects replays which are only
different in the encoded signature's case (lightningdevkit#4701).
* When `lightning-liquidity` is configured in the background processor, there
is no longer a stream of `Persisting LiquidityManager...` log spam (lightningdevkit#4246).
* Incomplete MPP keysend payments will no longer see their HTLCs held until
expiry (lightningdevkit#4558).
* `InvoiceRequestBuilder` will no longer accept a `quantity` of `0` for a
BOLT 12 `Offer`, allowing any quantity up to a bound (lightningdevkit#4667).
* `lightning-custom-message` handlers that return `Ok(None)` when asked to
deserialize a message in their defined range no longer cause panics (lightningdevkit#4709).
* Several spurious debug assertions were fixed (lightningdevkit#4537, lightningdevkit#4618, lightningdevkit#4026)
Security
========
0.2.3 fixes several underestimates of the anchor reserves required to ensure we
can reliably close channels, several denial-of-service vulnerabilities and a
sanitization issue.
* `Bolt11Invoice::recover_payee_pub_key` no longer panics if called on an
invoice which set an explicit public key, rather than relying on public key
recovery. Note that this method is called from
`PaymentParameters::from_bolt11_invoice` (lightningdevkit#4717).
* Maliciously-crafted unpayable invoices which have overflowing feerates will
no longer cause an `unwrap` failure panic (lightningdevkit#4716).
* Parsing an `LSPSDateTime` which is before 1970 no longer panics. This is
reachable when parsing messages from counterparties (lightningdevkit#4715).
* `possiblyrandom` did not properly generate random data except when it was
explicitly configured to. By default this means LDK is vulnerable to various
HashDoS attacks (lightningdevkit#4719).
* `OMNameResolver` will no longer panic when looking up payment instructions
which include unicode characters at the start of a TXT record (lightningdevkit#4718).
* When using the `anchor_channel_reserves` module to calculate reserves
required to pay for fees when closing anchor channels, zero-fee-commitment
channels were not considered. This could allow a counterparty to open many
channels, leaving us unable to properly force-close (lightningdevkit#4592).
* The `anchor_channel_reserves` module overestimated the value of `Utxo`s in
the wallet by ignoring the `TxIn` cost to spend them (lightningdevkit#4670).
* `PrintableString` did not properly sanitize unicode format characters,
allowing an attacker to corrupt the rendering of logs or UI (lightningdevkit#4593, lightningdevkit#4605).
* RGS data is now limited in how large of a graph it is able to cause a client
to store in memory. Note that RGS data is still considered a DoS vector in
general and you should only use semi-trusted RGS data (lightningdevkit#4713).
* Counterparty-provided strings in failure messages are no longer logged in
full, reducing the ability of such a counterparty to spam our logs (lightningdevkit#4714).
* Reading a corrupted `ChannelManager` or `ProbabilisticScorer` can no longer
cause us to allocate large amounts of memory (lightningdevkit#4712).
Thanks to Project Loupe for reporting most of the issues fixed in this release.
Conflicts resolved in:
* lightning/src/chain/channelmonitor.rs
* lightning/src/events/mod.rs
* lightning/src/ln/channelmanager.rs
* lightning/src/ln/mod.rs
* lightning/src/ln/offers_tests.rs
* lightning/src/ln/onion_utils.rs
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