Improper Authentication in authentik - CVE-2026-25748
Published: April 23, 2026
Vulnerability identifier: #VU127149
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: CVE-2026-25748
CWE-ID: CWE-287
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Authentik Security Inc
Affected software:
authentik
authentik
Detailed vulnerability description
The vulnerability allows a remote attacker to bypass authentication and gain access to the application.
The vulnerability exists due to improper authentication in the Proxy Provider forward authentication handling when processing a malformed session cookie behind Traefik or Caddy. A remote attacker can send a malformed session cookie to bypass authentication and gain access to the application.
Exploitation depends on the behavior of applications behind the Proxy Provider, particularly whether they require an X-Authentik header to be present.
How to mitigate CVE-2026-25748
Install security update from vendor's website.