GHSA-x3q4-9hxx-gx8m ApostropheCMS sanitize-html: nonTextTags discard region ends early on an implied close, letting <noscript> content render

• npm sanitize-html: < 2.18.0 → fixed in 2.18.0

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 `` 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 `` 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('', { allowedTags: ["div", "img"], allowedAttributes: { img: ["src"] }, nonTextTags: ["script", "style", "textarea", "option", "noscript"], }); // => '' ``` Chrome, given the same input, renders no `` — the whole payload is raw text inside the unclosed ``. Verified with Playwright, `srcdoc` into an iframe so the scripting flag is on. A `Hi ]]>Reset your password ``` htmlparser2 runs a CDATA token to `]]>`; Chrome ends a bogus comment at the first `>`, so the `` 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 passed and discarded. Something close to: ```js onclosetag: function (name, isImplied) { if (skipText) { if (isImplied) return; // an implied close must not end the region skipTextDepth--; … ```