CVE-2026-33495: Authentication Bypass in Ory Oathkeeper

An attacker exploiting this vulnerability could bypass authentication checks within Ory Oathkeeper. This is particularly concerning when Oathkeeper is deployed behind reverse proxies or CDNs. By manipulating the X-Forwarded-Proto header, an attacker could trick Oathkeeper into thinking a request is using HTTPS when it's actually HTTP, or vice versa. This could lead to unauthorized access to protected resources or services that rely on Oathkeeper for authentication. The impact is amplified if Oathkeeper is a central authentication point for multiple applications, as a successful exploit could compromise a wider range of systems.

1. Reserviert2026-03-20
2. Veröffentlicht2026-03-20
3. Geändert2026-03-27
4. EPSS aktualisiert2026-04-03

The primary mitigation is to upgrade to version 0.40.10-0.20260320084810-e9acca14a04d or later. If upgrading is not immediately feasible, consider temporarily disabling the serve.proxy.trustforwardedheaders configuration option. This will prevent Oathkeeper from trusting any X-Forwarded-* headers, effectively disabling the vulnerable functionality. Ensure your reverse proxy or CDN is properly configured to only forward trusted headers and that the protocol matches the original request. Monitor Oathkeeper logs for suspicious activity related to header manipulation.