authentik RAC: access any endpoint via an unrelated application

authentik is an open-source identity provider. Prior to 2026.2.6 and 2026.5.5, the Remote Access Control endpoint list returns every configured endpoint to any authenticated user regardless of which applications the user may access, and the response includes connection settings that can contain stored credentials. The endpoint listing does not apply the access controls governing the endpoints, and the connection flow does not confirm that an endpoint belongs to the Remote Access Control application through which it was launched. Any authenticated user can therefore read every endpoint together with its host and stored credentials and can open a connection to an endpoint belonging to another application. This exposes stored credentials for managed RDP, SSH, and VNC targets and grants interactive access to systems the user was never authorized to reach. Deployments that do not use the enterprise Remote Access Control provider are not affected. This issue is fixed in versions 2026.2.6 and 2026.5.5.