Improper access control in authentik - #VU131252
Published: May 12, 2026
authentik
Detailed vulnerability description
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to improper access control in the OAuth2/OpenID Connect provider configuration handling when processing the first authorization request for a provider with no redirect URIs configured. A remote attacker can send an authorization request with an attacker-controlled redirect_uri to disclose sensitive information.
User interaction is required to complete a legitimate OAuth2 flow after the redirect URI has been poisoned, and the impact extends to relying party applications because authorization codes can be redirected outside the identity provider's security scope.