CVE-2026-69153

EUVD-2026-52373

03.08.2026, 17:16

PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Prior to 8.5.19, if from is unset, an attacker can cause PreviousMap.loadFile() to read an unintended source-map file by supplying an absolute or directory-traversal sourceMappingURL. The resulting map’s sources and sourcesContent may then be exposed to the application. This issue is fixed in version 8.5.19.

Path Traversal

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
GitHub_M	CNA	6.3 MEDIUM	NETWORK	LOW	NONE	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Early Detection

Affected products identified ahead of NVD analysis through intelligence sources.

Vendor	Product	Version	Source
postcss	postcss	𝑥 < 8.5.19	CNA

Debian Releases

Debian Product

Codename

node-postcss

bookworm	vulnerable
bullseye	vulnerable
bullseye (security)	vulnerable
forky	vulnerable
sid	8.5.25+~cs10.2.23-1 fixed
trixie	vulnerable

Common Weakness Enumeration

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

References

https://github.com/postcss/postcss/commit/7beca139e70f9075c6b19700fcb00dd8033e5da8

https://github.com/postcss/postcss/releases/tag/8.5.19

https://github.com/postcss/postcss/security/advisories/GHSA-fxqj-rqcc-2cmp