CVE-2026-41305

Published: Apr 24, 2026Modified: Jun 17, 2026Deferred

6.1

Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Exploitability: 2.8 / Impact: 2.7

Source: security-advisories@github.com (Secondary)

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.

Related CWEs

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

References (3)

https://github.com/postcss/postcss/releases/tag/8.5.10

Source: security-advisories@github.com

https://github.com/postcss/postcss/security/advisories/GHSA-qx2v-qp2m-jg93

Source: security-advisories@github.com

https://github.com/postcss/postcss/security/advisories/GHSA-qx2v-qp2m-jg93

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

Timeline

No history available yet.