| Name | CVE-2026-41305 |
| Description | PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Versions prior to 8.5.10 do not escape `</style>` sequences when stringifying CSS ASTs. When user-submitted CSS is parsed and re-stringified for embedding in HTML `<style>` tags, `</style>` in CSS values breaks out of the style context, enabling XSS. Version 8.5.10 fixes the issue. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| node-postcss (PTS) | bullseye | 8.2.1+~cs5.3.23-8 | vulnerable |
| bullseye (security) | 8.2.1+~cs5.3.23-8+deb11u1 | vulnerable | |
| bookworm | 8.4.20+~cs8.0.23-1+deb12u1 | vulnerable | |
| trixie | 8.4.49+~cs9.2.32-1 | vulnerable | |
| forky | 8.5.12+~cs9.3.32-1 | fixed | |
| sid | 8.5.14+~cs9.3.34-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| node-postcss | source | (unstable) | 8.5.12+~cs9.3.32-1 |
[trixie] - node-postcss <no-dsa> (Minor issue)
[bookworm] - node-postcss <no-dsa> (Minor issue)
[bullseye] - node-postcss <postponed> (Minor issue; can be fixed in next update)
https://github.com/postcss/postcss/security/advisories/GHSA-qx2v-qp2m-jg93
https://github.com/postcss/postcss/commit/536c79e4b01e58a3a56b09c3c0cf2323f4b9a28b (8.5.10)