The twofactor_gauthenticator plugin for Roundcube is vulnerable to brute-forcing of the second...

The twofactor_gauthenticator plugin for Roundcube is vulnerable to brute-forcing of the second-factor code. Due to the lack of rate limiting, an attacker who obtains user's password can submit arbitrary 6-digit codes, resulting in second-factor bypass and unauthorized access to the system.

This issue was fixed in commit 4640889.