CVE-2026-9358 (GCVE-0-2026-9358)

Vulnerability from cvelistv5 – Published: 2026-05-24 05:30 – Updated: 2026-06-15 07:21 X_Open Source
VLAI
Title
postcss-selector-parser AST Serialization container.js toString recursion
Summary
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.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C
4.3 (Medium)
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
n/a postcss-selector-parser Affected: 6.1.0
Affected: 6.1.1
Affected: 6.1.2
Affected: 7.1.0
Affected: 7.1.1
Affected: 7.1.2
Unaffected: 6.1.3
Unaffected: 7.1.3
    cpe:2.3:a:postcss-selector-parser:postcss-selector-parser:*:*:*:*:*:*:*:*
Credits
bx33661 (VulDB User) VulDB CNA Team
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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