PostCSS has XSS via Unescaped </style> in its CSS Stringify Output

Description

No description available.

Recommendation

Update the postcss package to the latest compatible version. Followings are version details:

• Affected version(s): < 8.5.10
• Patched version(s): 8.5.10

References

• GHSA-qx2v-qp2m-jg93
• CVE-2026-41305
• CWE-79
• CAPEC-310
• OWASP 2021-A3
• OWASP 2021-A6

Related Issues

• ApostropheCMS: Stored XSS via CSS Custom Property Injection in @apostrophecms/color-field Escaping Style Tag Context - CVE-2026-33889
• Parse Server has a stored XSS filter bypass via Content-Type MIME parameter and missing XML extension blocklist entries - CVE-2026-32728
• Apostrophe has default XSS via `xmp` raw-text passthrough in `sanitize-html` - CVE-2026-44990
• Undici has Unbounded Memory Consumption in its DeduplicationHandler via Response Buffering that leads to DoS - CVE-2026-2581

You might also like:

How to Secure your NodeJs Express Javascript Application - part 1

How do hackers hack websites?

CSRF, XXE, and 12 Other Security Acronyms Explained

Tags:

npm

postcss