The twofactor_gauthenticator plugin for Roundcube is vulnerable to 2fa authentication bypass by...

The twofactor_gauthenticator plugin for Roundcube is vulnerable to 2fa authentication bypass by spoofed client address headers. Due to the lack of validation of the Client-IP and X-Forwarded-For headers, an attacker who obtains user's password can spoof a whitelisted IP address, resulting in the second factor being bypassed.

This issue was fixed in commit 4640889.