CVE-2025-35939
Craft CMS stores user-provided content in session files
CVE-2025-35939 is a medium vulnerability (CVSS 6.9) in Craft Cms, published May 7, 2025. CISA lists it as known to be exploited, since June 2, 2025. EUVD reports exploitation since June 2, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.35%, the 71st percentile. Fixed in craftcms/cms 5.7.5.
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.9
Craft CMS stores user-provided content in session files
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.
- Record
CVE-2025-35939- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-472
- Updated
- 2026-11-02
EUVDEUVD-2025-13951
6.9
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.
- Record
EUVD-2025-13951- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7vrx-9684-xrf2
6.9
Craft CMS stores arbitrary content provided by unauthenticated users in session files
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.
- Record
GHSA-7vrx-9684-xrf2- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:A - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:H - Weakness
- CWE-472
- Updated
- 2026-11-02
CISA KEV No score
Craft CMS External Control of Assumed-Immutable Web Parameter Vulnerability
Craft CMS contains an external control of assumed-immutable web parameter vulnerability. This vulnerability could allow an unauthenticated client to introduce arbitrary values, such as PHP code, to a known local file location on the server. This vulnerability could be chained with CVE-2024-58136 as represented by CVE-2025-32432.
- Record
CVE-2025-35939- Weakness
- CWE-472
- Updated
- 2026-11-02
NVD
6.9
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.
- Record
CVE-2025-35939- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-472
- Updated
- 2026-11-02
OSV
6.9
Craft CMS stores user-provided content in session files
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.
- Record
CVE-2025-35939- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-472
- Updated
- 2026-11-02
OSVGHSA-7vrx-9684-xrf2
6.9
Craft CMS stores arbitrary content provided by unauthenticated users in session files
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.
- Record
GHSA-7vrx-9684-xrf2- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:A - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:H - Weakness
- CWE-472
- Updated
- 2026-11-02
OSVCLSA-2026-1774313530 No score
TuxCare security update for craftcms/cms (10 CVEs)
TuxCare rebuilt craftcms/cms to address 10 CVEs. Fixed in 3.9.15-p1+tuxcare.
- Record
CLSA-2026-1774313530- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
craftcms/cmsPackagist |
5.0.0-alpha.1 up to 5.7.5 | 5.7.5 |
craftcms/cmsPackagist |
before 4.15.3 | 4.15.3 |
craftcms/cmsTuxCare:Packagist |
3.9.15 up to 3.9.15-p1+tuxcare | 3.9.15-p1+tuxcare |
craftcms/cmsPackagist |
5.0.0-alpha.1 up to 5.7.5, plus listed versions 5.0.05.0.0-RC15.0.0-alpha.105.0.0-alpha.115.0.0-alpha.12 Show 45 moreShow less5.0.0-alpha.135.0.0-alpha.25.0.0-alpha.35.0.0-alpha.45.0.0-alpha.55.0.0-alpha.65.0.0-alpha.75.0.0-alpha.85.0.0-alpha.95.0.0-beta.15.0.0-beta.105.0.0-beta.115.0.0-beta.25.0.0-beta.35.0.0-beta.45.0.0-beta.55.0.0-beta.65.0.0-beta.75.0.0-beta.85.0.0-beta.95.0.15.0.25.0.35.0.45.0.55.0.65.1.05.1.15.1.105.1.25.1.35.1.45.1.55.1.65.1.75.1.85.1.95.2.05.2.0-beta.15.2.0-beta.25.2.0-beta.35.2.0-beta.45.2.0-beta.55.2.0-beta.65.2.1 |
5.7.5 |
craftcms/cmsPackagist |
before 4.15.3, plus listed versions 1.0.26.11.2.0-alpha.23101.2.0-alpha.23121.2.0-alpha.23161.2.0-alpha.2318 Show 45 moreShow less1.2.0-alpha.23191.2.0-alpha.23221.2.0-alpha.23231.2.0-alpha.23241.2.0-alpha.23281.2.0-alpha.23291.2.0-alpha.23321.2.23331.2.23351.2.23361.2.23371.2.23391.2.23581.2.23631.2.23671.2.23711.2.23751.2.23871.2.23921.2.23961.2.23991.3.0-alpha.23611.3.0-alpha.23661.3.0-alpha.23721.3.0-alpha.23741.3.0-alpha.23771.3.0-alpha.23781.3.0-alpha.23801.3.0-alpha.23881.3.0-alpha.23941.3.0-alpha.23971.3.0-alpha.24011.3.0-alpha.24021.3.0-alpha.24051.3.0-alpha.24641.3.24091.3.24101.3.24151.3.24161.3.24181.3.24191.3.24201.3.24221.3.24561.3.2459 |
4.15.3 |
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-03 | exploitation | |
| 2026-11-02 | created | CVE List, EUVD, GitHub Advisories, CISA KEV, NVD, OSV |
References
github.com/craftcms/cms/pull/17220
github.com/craftcms/cms/releases/tag/4.15.3
github.com/craftcms/cms/releases/tag/5.7.5
cve.org/CVERecord?id=CVE-2025-35939
raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2025/va-25-147-01.json
cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-35939
Left out here: 1,076 versions. The JSON record has them.