{"timestamp":"2026-05-29T18:22:06.872944Z","id":"CVE-2026-9358","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}

[{"vendor":"n/a","product":"postcss-selector-parser","cpes":["cpe:2.3:a:postcss-selector-parser:postcss-selector-parser:*:*:*:*:*:*:*:*"],"modules":["AST Serialization"],"versions":[{"version":"6.1.0","status":"affected"},{"version":"6.1.1","status":"affected"},{"version":"6.1.2","status":"affected"},{"version":"7.1.0","status":"affected"},{"version":"7.1.1","status":"affected"},{"version":"7.1.2","status":"affected"},{"version":"6.1.3","status":"unaffected"},{"version":"7.1.3","status":"unaffected"}]}]

A vulnerability was determined in postcss up to 7.1.1. 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. 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)."

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.

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

A vulnerability was determined in postcss up to 7.1.1. 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. 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)."

AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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

(AV:N/AC:L/Au:N/C:N/I:N/A:P)

CWE-404

CWE-674

https://gist.github.com/bx33661/581e3a38134601c04e19b4dfc9b459b9

https://vuldb.com/submit/813080

https://vuldb.com/vuln/365321

https://vuldb.com/vuln/365321/cti