MEDIUMCVSS v4 5.3Vulnerability

CVE-2026-113654

## Summary `sanitize-html` discards the *content* of every element in `nonTextTags`. It delimits that region using htmlparser2's close events, and ignores the `isImplied` flag htmlparser2 passes it. Closing a still-open **ancestor** from inside a `<noscript>` makes htmlparser2 unwind its stack past the `noscript`; the synthetic implied close it emits on the way ends the discard region early, and everything after it is treated as ordinary body content. A browser with scripting enabled parses `<noscript>` content as **raw text**, so the same markup renders as inert text there. The sanitizer therefore emits elements the page itself would not have. ## Reproduction ```js const sanitizeHtml = require("sanitize-html"); sanitizeHtml('<div><noscript></div><img src="http://evil.test/t.gif"></noscript>', { allowedTags: ["div", "img"], allowedAttributes: { img: ["src"] }, nonTextTags: ["script", "style", "textarea", "option", "noscript"], }); // => '<div></div><img src="http://evil.test/t.gif" />' ``` Chrome, given the same input, renders **no** `<img>` — the whole payload is raw text inside the unclosed `<noscript>`. Verified with Playwright, `srcdoc` into an iframe so the scripting flag is on. A `<![CDATA[` variant hides the opening tag from the parser entirely and has the same effect: ``` <p>Hi</p><![CDATA[ x > <noscript>]]><a href="…">Reset your password</a><img src="…beacon.gif"></noscript> ``` htmlparser2 runs a CDATA token to `]]>`; Chrome ends a bogus comment at the first `>`, so the `<noscript>` after it is real to the browser and invisible to the parser. ## Where the behaviour is `index.js`: - `:154` — `nonTextTagsArray` (the default list, `['script','style','textarea','option','xmp']`). - `:638` — `onclosetag: function (name, isImplied)` — receives the flag. - `:644` — `skipTextDepth--` — decrements without consulting `isImplied`. ## Suggested fix Do not end a discard region on an implied close. htmlparser2 already distinguishes them; the flag is

Properties

Severity
medium
Summary
ApostropheCMS sanitize-html: nonTextTags discard region ends early on an implied close, letting <noscript> content render
Nvd fetched at
2026-10-20T21:14:08.448323+00:00
Cvss severity
MEDIUM
Cvss score
5.3
Retrieved at
2026-10-21T01:23:59+00:00
Ghsa published
2026-10-20T18:03:22Z
Source url
https://github.com/advisories/GHSA-x3q4-9hxx-gx8m
Ghsa updated
2026-10-20T18:03:24Z
Ghsa id
GHSA-x3q4-9hxx-gx8m
Last source
GitHub Advisory Database
Score
5.3
Cvss version
4.0
Cve id
CVE-2026-113654
Cvss vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
First seen by Signal
2026-10-20T21:15:35+00:00
Is ghsa only
false
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published at
2026-10-20T17:17:36.370
Last modified
2026-10-20T19:53:10.247

Related Entities (3)

AFFECTS (1)

→[Software]npm/sanitize-html

VULNERABLE_TO (1)

←[Software]npm/sanitize-html

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CVE-2026-113654 (CVSS v4 5.3) — Ninja Signal Threat Intelligence | Ninja Signal