Security: ZekStack/knot

Security

SECURITY.md

Security Policy

Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.

For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.

Threat model

Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.

For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.

Knot hashes are self-contained strings:

$knot$v1$c<cost>$<salt>$<hash>

The stored cost factor allows applications to verify older hashes and rehash them over time.

Cost guidance

Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.

Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.

Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.

Input handling

Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.

Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.

nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.

Reporting vulnerabilities

Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.

Include:

  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior

There aren't any published security advisories

, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n 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;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

Skip to content
Security: ZekStack/knot
Security

SECURITY.md

Security Policy
Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.
For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.
Threat model
Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.
For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.
Knot hashes are self-contained strings:
$knot$v1$c<cost>$<salt>$<hash>
The stored cost factor allows applications to verify older hashes and rehash them over time.
Cost guidance
Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.
Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.
Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.
Input handling
Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.
Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.
nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.
Reporting vulnerabilities
Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.
Include:
  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior
 There aren't any published security advisories


, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Security: ZekStack/knot
Security

SECURITY.md

Security Policy
Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.
For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.
Threat model
Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.
For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.
Knot hashes are self-contained strings:
$knot$v1$c<cost>$<salt>$<hash>
The stored cost factor allows applications to verify older hashes and rehash them over time.
Cost guidance
Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.
Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.
Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.
Input handling
Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.
Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.
nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.
Reporting vulnerabilities
Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.
Include:
  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior
 There aren't any published security advisories


, '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
Security: ZekStack/knot
Security

SECURITY.md

Security Policy
Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.
For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.
Threat model
Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.
For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.
Knot hashes are self-contained strings:
$knot$v1$c<cost>$<salt>$<hash>
The stored cost factor allows applications to verify older hashes and rehash them over time.
Cost guidance
Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.
Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.
Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.
Input handling
Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.
Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.
nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.
Reporting vulnerabilities
Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.
Include:
  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior
 There aren't any published security advisories


, '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" + '

Skip to content
Security: ZekStack/knot
Security

SECURITY.md

Security Policy
Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.
For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.
Threat model
Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.
For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.
Knot hashes are self-contained strings:
$knot$v1$c<cost>$<salt>$<hash>
The stored cost factor allows applications to verify older hashes and rehash them over time.
Cost guidance
Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.
Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.
Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.
Input handling
Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.
Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.
nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.
Reporting vulnerabilities
Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.
Include:
  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior
 There aren't any published security advisories


, '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('^' + ".*" + '

Skip to content
Security: ZekStack/knot
Security

SECURITY.md

Security Policy
Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.
For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.
Threat model
Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.
For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.
Knot hashes are self-contained strings:
$knot$v1$c<cost>$<salt>$<hash>
The stored cost factor allows applications to verify older hashes and rehash them over time.
Cost guidance
Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.
Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.
Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.
Input handling
Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.
Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.
nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.
Reporting vulnerabilities
Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.
Include:
  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior
 There aren't any published security advisories


, '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('^' + ".*" + '

Skip to content
Security: ZekStack/knot
Security

SECURITY.md

Security Policy
Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.
For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.
Threat model
Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.
For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.
Knot hashes are self-contained strings:
$knot$v1$c<cost>$<salt>$<hash>
The stored cost factor allows applications to verify older hashes and rehash them over time.
Cost guidance
Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.
Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.
Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.
Input handling
Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.
Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.
nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.
Reporting vulnerabilities
Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.
Include:
  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior
 There aren't any published security advisories


, '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); }
})();
})();

Skip to content
Security: ZekStack/knot
Security

SECURITY.md

Security Policy
Knot is an early-stage ESP32 password hashing library. Review the implementation, benchmark it on target hardware, and choose cost settings deliberately before using it in production firmware.
For current password storage guidance, see the OWASP Password Storage Cheat Sheet and NIST SP 800-63B.
Threat model
Knot is intended for local device login and constrained firmware flows where an ESP32 verifies a password-derived hash locally.
For cloud credential storage, prefer a server-side password hashing scheme such as Argon2id or scrypt where available. PBKDF2-HMAC-SHA256 is mainly a fallback path when preferred password hashing schemes are unavailable or unsuitable.
Knot hashes are self-contained strings:
$knot$v1$c<cost>$<salt>$<hash>
The stored cost factor allows applications to verify older hashes and rehash them over time.
Cost guidance
Cost 14 is the secure default and maps to 1,024,000 PBKDF2-HMAC-SHA256 iterations. It is not the demo or test setting.
Production firmware must benchmark cost 14 on the target ESP32 board and may lower the cost only with a documented latency and denial-of-service tradeoff.
Existing $knot$v1$c10$... hashes remain verifiable. They become rehash candidates when checked against the default cost 14.
Input handling
Knot hashes bytes, not characters. The const char * overloads hash bytes up to the first NUL byte. The const uint8_t * plus length overloads are binary-safe and can hash embedded NUL bytes.
Knot does not normalize Unicode. Applications that normalize passwords must do so consistently before hashing and verification.
nullptr passwords are rejected even when length is 0. Empty passwords are valid through hash("") or through a non-null byte pointer with length 0.
Reporting vulnerabilities
Report security issues privately to the repository maintainer. Do not open a public issue with exploit details before the maintainer has had time to investigate.
Include:
  • affected version or commit
  • reproduction steps
  • target board and framework version if ESP32-specific
  • expected and actual behavior
 There aren't any published security advisories