CVE-2026-58054: exploitation status and patch state
CVE-2026-58054 · CVSS 7.2 HIGH · EPSS <1%
MyBB 1.8.40 does not restrict which usergroup a limited Admin Control Panel user may assign when creating or editing users; the user module offers the Administrators group (gid 4) and its datahandler's verify_usergroup() unconditionally returns true. An admin holding only the delegated user-management permission can assign the Administrators group to an account and escalate to the full Administrator permission set.
Is CVE-2026-58054 exploited?
Not in the CISA KEV catalog.
EPSS puts exploitation in the next 30 days at <1%.
Public exploit code: none found in monitored sources.