CVE-2026-25748: Goauthentik Authentik

High severity, CVSS 7.5. EPSS: 0.9% chance of exploitation in the next 30 days.

authentik is an open-source identity provider. Prior to 2025.10.4 and 2025.12.4, with a malformed cookie it was possible to bypass authentication when using forward authentication in the authentik Proxy Provider when used in conjunction with Traefik or Caddy as reverse proxy. When a malicious cookie was used, none of the authentik-specific X-Authentik-* headers were set which depending on application can grant access to an attacker. authentik 2025.10.4 and 2025.12.4 fix this issue.

Affected products

• Goauthentik Authentik: before 2025.10.4 (fixed in 2025.10.4); from 2025.12.0, before 2025.12.4 (fixed in 2025.12.4)

Published 2026-02-12. Last modified 2026-06-17.