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fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365

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pcarleton merged 2 commits into
v1.xfrom
fix/redos-v1.x
Jan 7, 2026
Merged

fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom
fix/redos-v1.x

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@pcarletonpcarleton commented Jan 7, 2026

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Summary

Backport of the ReDoS fix from #1363 to the v1.x branch.

Changes

The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.

Security Impact

  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking

Changes Made

  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests

Testing

All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.

Version

Bumped to v1.25.2 for patch release.

Fixes#965

@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
pcarleton requested a review from a team as a code ownerJanuary 7, 2026 12:14
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⚠️ No Changeset found

Latest commit: 390df91

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

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commit: 390df91

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pcarleton commented Jan 7, 2026

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hmm changesets don't exist on the v1.x branch, we should probably fix that notification

@pcarleton
pcarleton merged commit b392f02 into v1.xJan 7, 2026
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@pcarleton
pcarleton deleted the fix/redos-v1.x branch January 7, 2026 14:37
@joeyorlandojoeyorlando mentioned this pull request Jan 7, 2026
Merged
joeyorlando added a commit to archestra-ai/archestra that referenced this pull request Jan 7, 2026
@joeyorlando
deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
<!-- CURSOR_SUMMARY -->
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, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) by pcarleton · Pull Request #1365 · modelcontextprotocol/typescript-sdk · GitHub
Skip to content
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365
Merged
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Jan 7, 2026
Merged
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Conversation
@pcarleton
@pcarletonpcarleton
commented
Jan 7, 2026

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Summary
Backport of the ReDoS fix from #1363 to the v1.x branch.
Changes
The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.
Security Impact
  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking
Changes Made
  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests
Testing
All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.
Version
Bumped to v1.25.2 for patch release.
Fixes#965
@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
pcarleton
requested a review
from a team
as a code ownerJanuary 7, 2026 12:14
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⚠️ No Changeset found
Latest commit: 390df91
Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.
Click here to learn what changesets are, and how to add one.
Click here if you're a maintainer who wants to add a changeset to this PR
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npm i https://pkg.pr.new/modelcontextprotocol/typescript-sdk/@modelcontextprotocol/sdk@1365

commit: 390df91
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hmm changesets don't exist on the v1.x branch, we should probably fix that notification
@pcarleton
pcarleton
merged commit b392f02
into
v1.xJan 7, 2026

7 checks passed

@pcarleton
pcarleton
deleted the

fix/redos-v1.x

branch
January 7, 2026 14:37
@joeyorlandojoeyorlando
mentioned this pull request
Jan 7, 2026
 Merged

joeyorlando added a commit
to archestra-ai/archestra
that referenced
this pull request
Jan 7, 2026
@joeyorlando
deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
<!-- CURSOR_SUMMARY -->
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> [!NOTE]
> <sup>[Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) is
generating a summary for commit
dc193e5. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) by pcarleton · Pull Request #1365 · modelcontextprotocol/typescript-sdk · GitHub
Skip to content
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365
Merged
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Jan 7, 2026
Merged
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Conversation
@pcarleton
@pcarletonpcarleton
commented
Jan 7, 2026

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Summary
Backport of the ReDoS fix from #1363 to the v1.x branch.
Changes
The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.
Security Impact
  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking
Changes Made
  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests
Testing
All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.
Version
Bumped to v1.25.2 for patch release.
Fixes#965
@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
pcarleton
requested a review
from a team
as a code ownerJanuary 7, 2026 12:14
@changeset-bot
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⚠️ No Changeset found
Latest commit: 390df91
Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.
Click here to learn what changesets are, and how to add one.
Click here if you're a maintainer who wants to add a changeset to this PR
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npm i https://pkg.pr.new/modelcontextprotocol/typescript-sdk/@modelcontextprotocol/sdk@1365

commit: 390df91
@pcarleton
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Jan 7, 2026

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hmm changesets don't exist on the v1.x branch, we should probably fix that notification
@pcarleton
pcarleton
merged commit b392f02
into
v1.xJan 7, 2026

7 checks passed

@pcarleton
pcarleton
deleted the

fix/redos-v1.x

branch
January 7, 2026 14:37
@joeyorlandojoeyorlando
mentioned this pull request
Jan 7, 2026
 Merged

joeyorlando added a commit
to archestra-ai/archestra
that referenced
this pull request
Jan 7, 2026
@joeyorlando
deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
<!-- CURSOR_SUMMARY -->
---
> [!NOTE]
> <sup>[Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) is
generating a summary for commit
dc193e5. Configure
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<!-- /CURSOR_SUMMARY -->
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) by pcarleton · Pull Request #1365 · modelcontextprotocol/typescript-sdk · GitHub
Skip to content
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365
Merged
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Jan 7, 2026
Merged
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Conversation
@pcarleton
@pcarletonpcarleton
commented
Jan 7, 2026

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Summary
Backport of the ReDoS fix from #1363 to the v1.x branch.
Changes
The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.
Security Impact
  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking
Changes Made
  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests
Testing
All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.
Version
Bumped to v1.25.2 for patch release.
Fixes#965
@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
pcarleton
requested a review
from a team
as a code ownerJanuary 7, 2026 12:14
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⚠️ No Changeset found
Latest commit: 390df91
Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.
Click here to learn what changesets are, and how to add one.
Click here if you're a maintainer who wants to add a changeset to this PR
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commit: 390df91
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hmm changesets don't exist on the v1.x branch, we should probably fix that notification
@pcarleton
pcarleton
merged commit b392f02
into
v1.xJan 7, 2026

7 checks passed

@pcarleton
pcarleton
deleted the

fix/redos-v1.x

branch
January 7, 2026 14:37
@joeyorlandojoeyorlando
mentioned this pull request
Jan 7, 2026
 Merged

joeyorlando added a commit
to archestra-ai/archestra
that referenced
this pull request
Jan 7, 2026
@joeyorlando
deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
<!-- CURSOR_SUMMARY -->
---
> [!NOTE]
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generating a summary for commit
dc193e5. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) by pcarleton · Pull Request #1365 · modelcontextprotocol/typescript-sdk · GitHub
Skip to content
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365
Merged
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Jan 7, 2026
Merged
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Conversation
@pcarleton
@pcarletonpcarleton
commented
Jan 7, 2026

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Summary
Backport of the ReDoS fix from #1363 to the v1.x branch.
Changes
The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.
Security Impact
  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking
Changes Made
  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests
Testing
All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.
Version
Bumped to v1.25.2 for patch release.
Fixes#965
@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
pcarleton
requested a review
from a team
as a code ownerJanuary 7, 2026 12:14
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⚠️ No Changeset found
Latest commit: 390df91
Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.
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hmm changesets don't exist on the v1.x branch, we should probably fix that notification
@pcarleton
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merged commit b392f02
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deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) by pcarleton · Pull Request #1365 · modelcontextprotocol/typescript-sdk · GitHub
Skip to content
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365
Merged
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Jan 7, 2026
Merged
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Conversation
@pcarleton
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Summary
Backport of the ReDoS fix from #1363 to the v1.x branch.
Changes
The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.
Security Impact
  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking
Changes Made
  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests
Testing
All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.
Version
Bumped to v1.25.2 for patch release.
Fixes#965
@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
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requested a review
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⚠️ No Changeset found
Latest commit: 390df91
Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.
Click here to learn what changesets are, and how to add one.
Click here if you're a maintainer who wants to add a changeset to this PR
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commit: 390df91
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hmm changesets don't exist on the v1.x branch, we should probably fix that notification
@pcarleton
pcarleton
merged commit b392f02
into
v1.xJan 7, 2026

7 checks passed

@pcarleton
pcarleton
deleted the

fix/redos-v1.x

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January 7, 2026 14:37
@joeyorlandojoeyorlando
mentioned this pull request
Jan 7, 2026
 Merged

joeyorlando added a commit
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Jan 7, 2026
@joeyorlando
deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
<!-- CURSOR_SUMMARY -->
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) by pcarleton · Pull Request #1365 · modelcontextprotocol/typescript-sdk · GitHub
Skip to content
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365
Merged
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Jan 7, 2026
Merged
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Conversation
@pcarleton
@pcarletonpcarleton
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Jan 7, 2026

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Summary
Backport of the ReDoS fix from #1363 to the v1.x branch.
Changes
The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.
Security Impact
  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking
Changes Made
  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests
Testing
All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.
Version
Bumped to v1.25.2 for patch release.
Fixes#965
@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
pcarleton
requested a review
from a team
as a code ownerJanuary 7, 2026 12:14
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⚠️ No Changeset found
Latest commit: 390df91
Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.
Click here to learn what changesets are, and how to add one.
Click here if you're a maintainer who wants to add a changeset to this PR
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npm i https://pkg.pr.new/modelcontextprotocol/typescript-sdk/@modelcontextprotocol/sdk@1365

commit: 390df91
@pcarleton
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hmm changesets don't exist on the v1.x branch, we should probably fix that notification
@pcarleton
pcarleton
merged commit b392f02
into
v1.xJan 7, 2026

7 checks passed

@pcarleton
pcarleton
deleted the

fix/redos-v1.x

branch
January 7, 2026 14:37
@joeyorlandojoeyorlando
mentioned this pull request
Jan 7, 2026
 Merged

joeyorlando added a commit
to archestra-ai/archestra
that referenced
this pull request
Jan 7, 2026
@joeyorlando
deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
<!-- CURSOR_SUMMARY -->
---
> [!NOTE]
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generating a summary for commit
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[here](https://cursor.com/dashboard?tab=bugbot).</sup>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
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[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
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filter: none !important;
}
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filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
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/* Scrollbars */
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::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
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e.preventDefault();
enabled = !enabled;
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removeDarkMode();
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var observer = new MutationObserver(function(mutations) {
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observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) by pcarleton · Pull Request #1365 · modelcontextprotocol/typescript-sdk · GitHub
Skip to content
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport) - #1365
Merged
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Jan 7, 2026
Merged
fix: prevent ReDoS in UriTemplate regex patterns (v1.x backport)#1365
pcarleton merged 2 commits into
v1.xfrom 
fix/redos-v1.x
Conversation
@pcarleton
@pcarletonpcarleton
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Jan 7, 2026

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Summary
Backport of the ReDoS fix from #1363 to the v1.x branch.
Changes
The exploded array handling regex patterns in UriTemplate were vulnerable to ReDoS (Regular Expression Denial of Service) attacks. Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking when matching malicious input.
Security Impact
  • CVE: CVE-2026-0621
  • Severity: Moderate
  • Attack Vector: A malicious URI with repeated commas could cause exponential backtracking
Changes Made
  • Fixed regex pattern on line 228 (empty operator, exploded)
  • Fixed regex pattern on line 238 (path operator, exploded)
  • Added ReDoS regression tests
Testing
All existing tests pass, plus two new security regression tests that verify the fix prevents the ReDoS vulnerability.
Version
Bumped to v1.25.2 for patch release.
Fixes#965
@pcarleton
fix: prevent ReDoS in UriTemplate regex patterns
646cfab
The exploded array handling regex patterns were vulnerable to ReDoS attacks.
Changed [^/]+ to [^/,]+ in the character class to prevent catastrophic backtracking.
CVE-2026-0621Fixes#965
@pcarleton
1.25.2
390df91
@pcarleton
pcarleton
requested a review
from a team
as a code ownerJanuary 7, 2026 12:14
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⚠️ No Changeset found
Latest commit: 390df91
Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.
Click here to learn what changesets are, and how to add one.
Click here if you're a maintainer who wants to add a changeset to this PR
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commit: 390df91
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hmm changesets don't exist on the v1.x branch, we should probably fix that notification
@pcarleton
pcarleton
merged commit b392f02
into
v1.xJan 7, 2026

7 checks passed

@pcarleton
pcarleton
deleted the

fix/redos-v1.x

branch
January 7, 2026 14:37
@joeyorlandojoeyorlando
mentioned this pull request
Jan 7, 2026
 Merged

joeyorlando added a commit
to archestra-ai/archestra
that referenced
this pull request
Jan 7, 2026
@joeyorlando
deps: addressCVE-2026-0621(#1898)
9b95312
See modelcontextprotocol/typescript-sdk#1365
Closes https://github.com/archestra-ai/archestra/security/dependabot/70
<!-- CURSOR_SUMMARY -->
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> [!NOTE]
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