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.
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version



Related Resources
References
https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25748.json, https://github.com/goauthentik/authentik/releases/tag/version%2F2025.10.4, https://github.com/goauthentik/authentik/releases/tag/version%2F2025.12.4, https://github.com/goauthentik/authentik/security/advisories/GHSA-fj56-5763-j8pp, https://nvd.nist.gov/vuln/detail/CVE-2026-25748
