Privilege escalation in Goauthentik Authentik

CVE-2026-40172

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 change_user on a target user to assign arbitrary groups through UserSerializer, including groups with is_superuser=True, without requiring enable_group_superuser, leading to privilege escalation. This bypasses the stricter permission model enforced in group-management paths and enables delegated user-management permissions to escalate target users to administrator-equivalent privilege. Users with permissions to update groups or permissions to update users are able to add themselves or other users they have permissions on to users which have superuser permissions. This issue has been fixed in versions 22025.12.5 and 2026.2.3.

Vulnerability class: Privilege Escalation

EPSS: 0.005 (43.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-40172?
CVE-2026-40172 is a high-severity vulnerability in Goauthentik Authentik, classified under Improper Privilege Management. CVSS score: 8.1/10. Published 2026-05-22.
How severe is CVE-2026-40172?
High severity. CVSS v3 base score is 8.1 out of 10.