UsersWP <= 1.2.78 - Unauthenticated Account Access via Predictable Dummy User Password Disclosed through Registration Form Hash

The UsersWP – Front-end login form, User Registration, User Profile & Members Directory plugin for WordPress is vulnerable to unauthorized account access via Use of Predictable Password in all versions up to, and including, 1.2.78 The vulnerability exists because `get_dummy_user_passowrd()` derives the shared password for all 25 built-in dummy user accounts as the first 15 characters of `substr(hash('SHA256', AUTH_KEY . site_url()), 0, 25)`, while the full 25-character value of that same hash is simultaneously embedded in the hidden `uwp_register_hash` field rendered on every registration form response — reachable without authentication via both the public `/register/` page and the `wp_ajax_nopriv_uwp_ajax_register_form` AJAX handler, even when user registration is disabled. This makes it possible for unauthenticated attackers to recover the dummy user password directly from a single HTTP request and use it to authenticate as any of the 25 built-in dummy accounts (such as antawn, chynna, or kiki) through `wp-login.php`, potentially achieving privilege escalation if any dummy account holds an elevated role. Exploitation requires that an administrator has previously created dummy users via the plugin's Tools page.

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: UsersWP 1.2.79 closes this, and updating the plugin is the step that ends it.

• Login Security
• Alerts