GHSA-246W-JGMQ-88FG openvpn-auth-oauth2 returns FUNC_SUCCESS on client-deny, allowing unauthenticated VPN access

Summary When openvpn-auth-oauth2 is deployed in the experimental plugin mode shared library loaded by OpenVPN via the plugin directive, clients that do not support WebAuth/SSO e.g., the openvpn CLI on Linux are incorrectly admitted to the VPN despite being denied by the authentication logic. The...