MyBB Limited ACP-to-Admin Privilege Escalation via usergroup=4 POST

Ibrahim Saud@tektrix

•updated Jun 29, 2026•0•0•21

Detects exploitation attempts of the MyBB limited Admin CP-to-Admin privilege escalation vulnerability. The detection looks for unauthorized HTTP POST requests to the user management module that assign the Administrator group (gid=4) to a new user, or access to sensitive super-admin-only modules by accounts that should not have such permissions. It also flags requests containing known PoC artifact identifiers.