description: The PlexTrac platform prior to version 1.28.0 allows for username enumeration via HTTP response times on invalid login attempts for users configured to use the PlexTrac authentication provider. Login attempts for valid, unlocked users configured to use PlexTrac as their authentication provider take significantly longer than those for invalid users, allowing for valid users to be enumerated by an unauthenticated remote attacker. Note that the lockout policy implemented in Plextrac version 1.17.0 makes it impossible to distinguish between valid, locked user accounts and user accounts that do not exist, but does not prevent valid, unlocked users from being enumerated.