CVE-2026-9358

Name	CVE-2026-9358
Description	A vulnerability was determined in postcss-selector-parser up to 6.1.2/7.1.2. Affected is the function toString of the file src/selectors/container.js of the component AST Serialization. Executing a manipulation can lead to uncontrolled recursion. It is possible to launch the attack remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 6.1.3 and 7.1.3 is able to address this issue. This patch is called 5bc698cef66f8abd12610dc623e5d67cbc0f869d. It is suggested to upgrade the affected component. The vendor explains, that according to his definition "DoS on server-side on user-generated CSS is low risk for us (since most users compile own CSS with PostCSS)." The commits were backported to 6.x branch, which was the most downloaded version.
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)
Debian Bugs	1139161

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
node-css-loader (PTS)	bullseye	5.0.1+~cs14.0.5-1	vulnerable
	bookworm	6.7.2+~cs14.0.11-1	vulnerable
	trixie	6.8.1+~cs14.0.17-1	vulnerable
	forky, sid	6.8.1+~cs14.0.17-2	vulnerable

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
node-css-loader	source	(unstable)	(unfixed)			1139161

Notes

[trixie] - node-css-loader <no-dsa> (Minor issue)
[bookworm] - node-css-loader <no-dsa> (Minor issue)
[bullseye] - node-css-loader <postponed> (Minor issue)
https://gist.github.com/bx33661/581e3a38134601c04e19b4dfc9b459b9
postcss-selector-parser embedded in node-css-loader