Vulnerability Description
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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Goauthentik | Authentik | < 2025.10.4 |
Related Weaknesses (CWE)
References
- https://github.com/goauthentik/authentik/releases/tag/version%2F2025.10.4ProductRelease Notes
- https://github.com/goauthentik/authentik/releases/tag/version%2F2025.12.4ProductRelease Notes
- https://github.com/goauthentik/authentik/security/advisories/GHSA-fj56-5763-j8ppVendor Advisory
FAQ
What is CVE-2026-25748?
CVE-2026-25748 is a vulnerability with a CVSS score of 8.6 (HIGH). 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 Pro...
How severe is CVE-2026-25748?
CVE-2026-25748 has been rated HIGH with a CVSS base score of 8.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-25748?
Check the references section above for vendor advisories and patch information. Affected products include: Goauthentik Authentik.