SSL-VPN MFA Bypass in SonicWALL SSL-VPN can arise in specific cases due to the separate handling of UPN (User Principal Name) and SAM (Security Account Manager) account names when integrated with Microsoft Active Directory, allowing MFA to be configured independently for each login method and potentially enabling attackers to bypass MFA by exploiting the alternative account name.
The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error.