CVE-2025-35939 on CISA KEV

Craft CMS stores arbitrary content provided by unauthenticated users in session files. This content could be accessed and executed, possibly using an independent vulnerability. Craft CMS redirects requests that require authentication to the login page and generates a session file

01What CISA says about this vulnerability

Craft CMS stores arbitrary content provided by unauthenticated users in session files. This content could be accessed and executed, possibly using an independent vulnerability. Craft CMS redirects requests that require authentication to the login page and generates a session file on the server at '/var/lib/php/sessions'. Such session files are named 'sess_[session_value]', where '[session_value]'…

02Required action — verbatim from CISA

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

03Notes & references

• github.com — https://github.com/craftcms/cms/pull/17220
• github.com — https://github.com/craftcms/cms/releases/tag/4.15.3
• github.com — https://github.com/craftcms/cms/releases/tag/5.7.5
• www.cve.org — https://www.cve.org/CVERecord?id=CVE-2025-35939
• raw.githubusercontent.com — https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2025/…

04SARA's analyst layer — why this matters

This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.

05Affected products (summary)

Vendor	Product	Versions
Craft	CMS	0, 5.7.5, 0, 4.15.3

06Detection

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