CVE-2026-40172 authentik: Privilege Escalation via User PATCH: Superuser Group Assignment Bypasses enable_group_superuser

authentik is an open-source identity provider. In versions prior to 2025.12.5 and 2026.2.0-rc1 through 2026.2.2, the PATCH /api/v3/core/users/pk/ API allows a caller with changeuser on a target user to assign arbitrary groups through UserSerializer, including groups with issuperuser=True, without...