Description

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]` is provided to the client in a `Set-Cookie` response header. Craft CMS stores the return URL requested by the client without sanitizing parameters. Consequently, an unauthenticated client can introduce arbitrary values, such as PHP code, to a known local file location on the server. Craft CMS versions 5.7.5 and 4.15.3 have been released to address this issue.

Classification

CVE ID: CVE-2025-35939

CVSS Base Severity: MEDIUM

CVSS Base Score: 5.3

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected Products

Vendor: Craft

Product: CMS

Exploit Prediction Scoring System (EPSS)

EPSS Score: 39.61% (probability of being exploited)

EPSS Percentile: 97.11% (scored less or equal to compared to others)

EPSS Date: 2025-06-05 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-35939
https://github.com/craftcms/cms/pull/17220
https://github.com/craftcms/cms/releases/tag/4.15.3
https://github.com/craftcms/cms/releases/tag/5.7.5

Timeline