In server mode pgAdmin 4 locks an internal account after MAX_LOGIN_ATTEMPTS failed logins (3 by default). The limit could be bypassed, giving an unauthenticated attacker an unlimited number of password guesses against any internal account, including the administrator's, in the default configuration: Flask-Security registers its own views next to pgAdmin's. A login submitted to its /login view was checked and logged in without pgAdmin's failed login count or lock. Its /verify view checked a signed-in user's password without limit, its /change view changed a password without pgAdmin's change password permission or re-encrypting the user's saved server passwords, and its /reset views sent and applied password resets for accounts that are not internal or are locked. The internal account was…