Python Social Auth is a social authentication/registration mechanism. Prior to version 5.0.0, the LoginRadius backend did not validate OAuth state during the authentication flow. Applications using this backend were vulnerable to login CSRF. An attacker could cause a victim's browser session to complete authentication using an attacker-controlled LoginRadius token, making the victim authenticated as the attacker's LoginRadius identity. The issue affects only applications using the LoginRadius backend. The issue has been fixe in version 5.0.0 by enabling callback state validation for the LoginRadius backend.