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.
https://www.vulncheck.com/advisories/grav-login-plugin-privilege-escalation-via-profile-update
https://github.com/getgrav/grav/security/advisories/GHSA-h33v-82r9-v8pm
Published: 2026-07-22
Updated: 2026-07-22
Base Score: 9
Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C
Severity: High
Base Score: 8.8
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity: High
Base Score: 8.7
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00442