Executive brief
The Grav Login plugin exposes an account unlock feature via its API that clears failed login attempt counters. The feature requires api.users.write permission but fails to verify that the calling user has authority over the target account. An attacker with basic user-management permissions can repeatedly unlock admin super-user accounts, removing brute-force protection from the highest-privilege accounts without requiring equivalent permissions themselves.
Technical details
This is a privilege escalation vulnerability caused by missing authorization checks in the onApiUserListRowAction unlock handler. The handler verifies the caller has api.users.write permission (delegated from the API plugin layer), but does not verify the target account's privilege level before clearing its lockout counters. An attacker with api.users.write permission—a separate, lower privilege than admin.super—can invoke the unlock action on any account, including admin.super accounts, effectively removing brute-force protection from the highest-value targets in the system. The vulnerability requires an authenticated attacker with api.users.write permission to exploit. Patch 1.0.16 is available.
Affected products
- Grav Login plugin before 1.0.16
Timeline
- 2026-08-25: disclosed: CVE-2026-56710 published
- 2026-08-10: patched: Patch version 1.0.16 released