PT-2026-42916 · Npm · Postcss

Bx33661 · Published 2026-05-24 · Updated 2026-05-24 · CVE-2026-9358

Positive Technologies (AI Summary)

CVSS v2.0

5.0

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions postcss versions prior to 7.1.2

Description An issue exists in the AST Serialization component within the toString() function of the src/selectors/container.js file. A remote attacker can perform a manipulation that leads to uncontrolled recursion, potentially causing a denial of service. This risk is primarily applicable to server-side environments processing user-generated CSS.

Recommendations Update to version 7.1.2 or later. As a temporary workaround, restrict the processing of user-generated CSS through the toString() function in the src/selectors/container.js file.

Exploit

Fix

Uncontrolled Recursion

Improper Resource Release

Weakness Enumeration

CWE-674

CWE-404

Related Identifiers

CVE-2026-9358

RHSA-2026:22934

Affected Products

Postcss

References · 17

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/9xxx/CVE-2026-9358.json · Exploit
• 🔥 https://gist.github.com/bx33661/581e3a38134601c04e19b4dfc9b459b9 · Exploit
• https://github.com/postcss/postcss-selector-parser/commit/5bc698cef66f8abd12610dc623e5d67cbc0f869d · Patch
• https://github.com/postcss/postcss-selector-parser/releases/tag/7.1.3 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-9358 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-9358 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-9358 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-9358 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-9358 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-9358 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-9358 · Vendor Advisory
• https://twitter.com/CVEnew/status/2058530614605959173 · Twitter Post
• https://vuldb.com/cve/CVE-2026-9358 · Note
• https://vuldb.com/vuln/365321/cti · Note
• https://t.me/CVEtracker/54754 · Telegram Post