CVE-2025-49331

Executive Summary

CVE-2025-49331 is a critical deserialization of untrusted data vulnerability in the WordPress plugin eCommerce Product Catalog by impleCode, affecting versions up to and including 3.4.3. This vulnerability allows an unauthenticated attacker to perform Object Injection via deserialization of untrusted data, potentially leading to remote code execution, data exfiltration, or complete site compromise. The vulnerability is classified under CWE-502 (Deserialization of Untrusted Data) and carries a CVSS score of 7.2 (High). As of this report, no official patch has been released, and no public proof-of-concept (PoC) or exploit code is available. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the severity warrants immediate attention.

Supply Chain & Package Security

This vulnerability affects the WordPress plugin ecosystem. The plugin is distributed via the official WordPress Plugin Directory and can be installed directly from the WordPress admin dashboard. Since no patch is available, site administrators must consider removing or disabling the plugin until a fix is released. The lack of a patch and the high severity make this a significant supply chain risk for any WordPress site using this plugin.

CVSS Breakdown & Threat Level

• CVSS Score: 7.2 (High)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – Vulnerability does not affect other components.
• Confidentiality (C): High (H) – Full data access possible.
• Integrity (I): High (H) – Full data modification possible.
• Availability (A): High (H) – Full system disruption possible.

Threat Level: Critical. The combination of network exploitability, no authentication, and high impact makes this a top-priority vulnerability for remediation.

Deep Dive & Mechanics

The vulnerability resides in the deserialization of untrusted data within the eCommerce Product Catalog plugin. The plugin likely uses PHP’s unserialize() function on user-supplied input without proper validation or sanitization. This allows an attacker to inject arbitrary PHP objects, leading to Object Injection.

Attack Flow:

1. An attacker sends a crafted HTTP request containing a serialized PHP object.
2. The plugin’s code calls unserialize() on the attacker-controlled data.
3. The deserialized object triggers magic methods (e.g., __wakeup(), __destruct()) that can execute arbitrary code, read/write files, or perform other malicious actions.

Root Cause: The plugin fails to validate or sanitize serialized data before deserialization. Common vulnerable patterns include:

• unserialize($_POST['data']);
• unserialize($_GET['option']);
• unserialize($request_body);

Exploitation Prerequisites:

• WordPress site with eCommerce Product Catalog plugin version <= 3.4.3.
• Network access to the site.
• No authentication required.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code is presumed to be present in all versions <= 3.4.3. A typical vulnerable pattern in WordPress plugins is:

Vulnerable Code (PHP):

// Vulnerable: Direct unserialize of user input
$data = unserialize($_POST['product_data']);

Patched Code (Hypothetical):

// Patched: Use JSON instead of serialization
$data = json_decode(stripslashes($_POST['product_data']), true);
// Or validate input before unserialize
$data = maybe_unserialize(sanitize_text_field($_POST['product_data']));

The maybe_unserialize() function in WordPress is safer but still not recommended for untrusted data. The best practice is to avoid unserialize() entirely and use JSON or other safe serialization formats.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

1. Install WordPress with eCommerce Product Catalog plugin version 3.4.3.
2. Identify the vulnerable endpoint (e.g., /wp-admin/admin-ajax.php or a custom REST endpoint).
3. Craft a malicious serialized PHP object using a gadget chain (e.g., from WordPress core or plugin classes).

Exploit Example (PHP):

<?php
// Example gadget chain for WordPress (hypothetical)
class WP_Object {
    public $hook;
    public function __wakeup() {
        if (isset($this->hook)) {
            eval($this->hook);
        }
    }
}

$payload = new WP_Object();
$payload->hook = 'system("id");';
echo serialize($payload);
?>

Exploit Request:

POST /wp-admin/admin-ajax.php HTTP/1.1
Host: target.com
Content-Type: application/x-www-form-urlencoded

action=product_catalog_action&product_data=O:10:"WP_Object":1:{s:4:"hook";s:14:"system("id");";}

Note: No public PoC exists; this is a conceptual example.

Blue Team (Defensive)

Detection:

• Monitor for unusual serialized PHP objects in HTTP requests (e.g., strings starting with O:, a:, s:).
• Look for requests to plugin-specific endpoints with suspicious payloads.
• Use WAF rules to block unserialize-like patterns.

Mitigation:

• Disable or remove the plugin immediately.
• Implement a Web Application Firewall (WAF) with rules to block serialized PHP objects.
• Monitor logs for exploitation attempts.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP requests containing serialized PHP objects (e.g., O:, a:, s:).
  • Requests to /wp-admin/admin-ajax.php with action=product_catalog_action or similar.
  • Unusual POST parameters like product_data, option, data containing serialized strings.

• File IOCs:

  • Unexpected PHP files in wp-content/uploads/ or wp-content/plugins/.
  • Modified .htaccess files with malicious redirects.
  • New admin users created.

• System IOCs:

  • Unusual outbound connections from the web server.
  • High CPU usage from PHP processes.
  • Unexpected cron jobs or scheduled tasks.

Detection Engineering

YARA Rule

rule CVE_2025_49331_Deserialization {
    meta:
        description = "Detects serialized PHP objects in HTTP requests targeting eCommerce Product Catalog"
        author = "Valters IT"
        date = "2025-04-01"
        cve = "CVE-2025-49331"
    strings:
        $serialized = /O:\d+:"[^"]+":\d+:\{/
        $plugin_path = /ecommerce-product-catalog/
        $action = /product_catalog_action/
    condition:
        $serialized and ($plugin_path or $action)
}

Sigma Rule

title: CVE-2025-49331 - Deserialization Attempt in eCommerce Product Catalog
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects HTTP requests containing serialized PHP objects targeting the vulnerable plugin
author: Valters IT
date: 2025-04-01
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'admin-ajax.php'
        cs-uri-query|contains: 'action=product_catalog_action'
        cs-body|contains: 'O:'
    condition: selection
falsepositives:
    - Legitimate use of serialized data (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-49331 - eCommerce Product Catalog Deserialization Attempt"; flow:to_server,established; content:"POST"; http_method; content:"admin-ajax.php"; http_uri; content:"action=product_catalog_action"; http_client_body; pcre:"/O:\d+:\"[^\"]+\":\d+:\{/"; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable or remove the eCommerce Product Catalog plugin until a patch is released.
2. Implement a WAF with rules to block serialized PHP objects.
3. Monitor logs for exploitation attempts.

Long-term Fix:

• Await an official patch from impleCode. Once available, update to the patched version immediately.
• If the plugin is no longer maintained, consider migrating to an alternative product catalog plugin.

General Best Practices:

• Never use unserialize() on untrusted data.
• Use JSON or other safe serialization formats.
• Regularly update all WordPress plugins and themes.
• Implement input validation and sanitization.

Valters IT
Securing Digital Frontiers