Auth bypass in Goauthentik Authentik
CVE-2026-25748
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.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.009 (57.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.009 · change: +0.002
Affected products
- Goauthentik Authentik — versions >= 2025.10.0-rc1, < 2025.10.4, >= 2025.10.0-rc1, < 2025.12.4
Weakness classification (CWE)
References
- github.com/goauthentik/authentik/security/advisories/GHSA-fj56-5763-j8pp (Vendor Advisory)
- github.com/goauthentik/authentik/releases/tag/version/2025.10.4 (Product, Release Notes)
- github.com/goauthentik/authentik/releases/tag/version/2025.12.4 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-25748?
- CVE-2026-25748 is a high-severity vulnerability in Goauthentik Authentik, classified under Improper Authentication. CVSS score: 8.6/10. Published 2026-02-12.
- How severe is CVE-2026-25748?
- High severity. CVSS v3 base score is 8.6 out of 10.