CVE-2025-35939
Craft CMS stores arbitrary content provided by unauthenticated users in session files
Exploited in the wild
This vulnerability is on a Known Exploited Vulnerabilities catalogue, added 2025-06-02. Federal due date: 2025-06-23.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | craftcms/cms | >= 5.0.0-alpha.1, < 5.7.5 | 5.7.5 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Craftcms | Craft Cms | before 4.15.3 from 5.0.0 before 5.7.5 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- CISA KEV catalog
- 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
- https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2025/va-25-147-01.json
- https://www.cve.org/CVERecord?id=CVE-2025-35939
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-35939
- https://github.com/advisories/GHSA-7vrx-9684-xrf2
- https://nvd.nist.gov/vuln/detail/CVE-2025-35939
- https://github.com/craftcms/cms/commit/e4c7bac8f31010aee048409f9ef6f744a83146b2