Grav Login Plugin 3.8.11 Privilege Escalation via Profile Update
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Privilege escalation
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-269.
Summary
The Grav Login plugin (grav-plugin-login) versions <= 3.8.11 contain a privilege escalation flaw in the authenticated profile self-update handler (processUserProfile(), the update_user task). Unlike the registration handler, this handler does not strip privilege fields ('groups','access') from user-submitted form data before persisting them. When an administrator has added 'groups' and/or 'access' to plugins.login.user_registration.fields and the default 'regular'/DataUser account backend is in use, a low-privilege authenticated user can POST crafted profile form data (e.g. access[admin][super]=true) to escalate to super-admin, enabling admin panel access, scheduler abuse (RCE), and Twig evaluation. Fixed in 3.8.12.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA grav (getgrav) Fixed in 3.8.12
Timeline
- 2026-10-02 Threatist record created from CVE-2026-65603
- 2026-10-03 Alias added: GHSA-38mm-mxvc-j98q
References
More getgrav vulnerabilities
- TI-2026-30893 Grav: Privilege Escalation via Missing Server-Side Validation of groups/access CVSS 3.1CRITICAL 9.4
- TI-2025-28971 Cross Site Scripting vulnerability in grav v.1.7.48 and before allows an attacker to… CVSS 3.1CRITICAL 9.8
- TI-2021-04523 Unauthenticated Arbitrary YAML Write/Update leads to Code Execution CVSS 3.1CRITICAL 9.8
- TI-2026-50940 Grav CMS before 2.0.16 Origin Validation Bypass via Referer CVSS 4.0CRITICAL 9.3
- TI-2026-46446 Grav before 2.0.7 Remote Code Execution via Blueprint dynamicData CVSS 4.0CRITICAL 9.3
- TI-2021-22428 GravCMS 1.10.7 - Arbitrary YAML Write/Update (Unauthenticated) (2) CVSS 4.0CRITICAL 9.3
Sources
- CVE-2026-65603 · CVE Program
- CVE-2026-65603 · NVD
- FIRST EPSS
- GHSA-38mm-mxvc-j98q · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences