OpenEMR before 8.5.0 lacks rate limiting or lockout on TOTP submission, allowing attackers with a valid password to brute-force the 6-digit…

OpenEMR before 8.5.0 lacks rate limiting or lockout on TOTP submission, allowing attackers with a valid password to brute-force the 6-digit MFA code. Attackers can script repeated POST requests to main_screen.php or the OAuth2 authorization flow with re-submitted hidden credentials to bypass two-factor authentication.