CVE-2025-35939: Craft CMS stores arbitrary content provided by unauthenticated users in session files

medium KEV Affects craftcms/cms. Feed 2026.10.29.4, updated 2026-10-29; published 2025-05-08; advisory modified 2025-10-22; listed on CISA KEV 2025-06-02.

Craft CMS stores arbitrary content provided by unauthenticated users in session files

Package: craftcms/cms Composer
Affected versions: >=5.0.0-alpha.1 and <5.7.5 or <4.15.3
Fixed in: 5.7.5, 4.15.3
Severity: medium CVSS 5.3
Exploitation: KEV listed by CISA as actively exploited · EPSS 1% (71.4th percentile)
Published: 2025-05-08
Source: osv.dev

References

CWE-472

NVD record craftcms/cms advisories

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