grav-plugin-login (the Grav CMS Login plugin) versions >= 3.8.7 and < 3.9.7 allow the two-factor authentication challenge to be bypassed for content gated by the authenticated() Twig function or the [authenticated] shortcode. On sites with 2FA enabled, Login::isAuthenticated() checked only the session flag indicating that the password step had succeeded, not the flag indicating that login had completed, so a session sitting at the 2FA code prompt was treated as fully authenticated. An attacker who knows a member's password but cannot answer that member's second factor can therefore read member-only content rendered by the no-argument authenticated() or group authenticated(null, 'group') forms and by [authenticated]; the inverse [guest] shortcode is likewise evaluated too early. Impact is…