Cross-site Scripting (XSS) Affecting node-postcss package, versions <8.5.12+~cs9.3.32-1


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.03% (10th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-NODEPOSTCSS-16300171
  • published26 Apr 2026
  • disclosed24 Apr 2026

Introduced: 24 Apr 2026

NewCVE-2026-41305  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Debian:unstable node-postcss to version 8.5.12+~cs9.3.32-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream node-postcss package and not the node-postcss package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

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 &lt;/style&gt; sequences when stringifying CSS ASTs. When user-submitted CSS is parsed and re-stringified for embedding in HTML &lt;style&gt; tags, &lt;/style&gt; in CSS values breaks out of the style context, enabling XSS. Version 8.5.10 fixes the issue.

CVSS Base Scores

version 3.1