CVE-2026-9358
Severity CVSS v4.0:
LOW
Type:
CWE-404
Improper Resource Shutdown or Release
Publication date:
24/05/2026
Last modified:
15/06/2026
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.
Impact
Base Score 4.0
2.10
Severity 4.0
LOW
Base Score 3.x
4.30
Severity 3.x
MEDIUM
Base Score 2.0
5.00
Severity 2.0
MEDIUM
References to Advisories, Solutions, and Tools
- https://gist.github.com/bx33661/581e3a38134601c04e19b4dfc9b459b9
- https://github.com/postcss/postcss-selector-parser/commit/5bc698cef66f8abd12610dc623e5d67cbc0f869d
- https://github.com/postcss/postcss-selector-parser/releases/tag/7.1.3
- https://vuldb.com/cve/CVE-2026-9358
- https://vuldb.com/submit/813080
- https://vuldb.com/vuln/365321
- https://vuldb.com/vuln/365321/cti