CVE-2024-23512: Wpxpo Wowstore Deserialization Vulnerability

CVE-2024-23512 Overview

CVE-2024-23512 is a critical PHP Object Injection vulnerability affecting the ProductX – WooCommerce Builder & Gutenberg WooCommerce Blocks plugin for WordPress. This Deserialization of Untrusted Data vulnerability allows attackers to inject malicious serialized PHP objects into the application, potentially leading to complete site compromise.

The vulnerability exists due to improper handling of user-supplied serialized data within the ProductX plugin. When untrusted data is deserialized without adequate validation, attackers can manipulate object properties and exploit existing class methods (known as "gadget chains") to achieve arbitrary code execution, file manipulation, or database access.

Critical Impact

This vulnerability allows unauthenticated remote attackers to potentially achieve remote code execution on vulnerable WordPress installations running ProductX versions through 3.1.4, requiring no user interaction or privileges.

Affected Products

• wpxpo WowStore (ProductX – WooCommerce Builder & Gutenberg WooCommerce Blocks) versions through 3.1.4
• WordPress installations with the affected plugin installed
• WooCommerce-based e-commerce sites using ProductX for store building

Discovery Timeline

• 2024-02-12 - CVE-2024-23512 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-23512

Vulnerability Analysis

This vulnerability falls under CWE-502 (Deserialization of Untrusted Data), a well-known class of security flaws that can have severe consequences in PHP applications. The ProductX plugin fails to properly validate and sanitize serialized data before processing it through PHP's unserialize() function or similar deserialization mechanisms.

PHP Object Injection vulnerabilities are particularly dangerous in WordPress environments because the large ecosystem of plugins and themes often provides numerous "gadget chains" - existing class methods that can be chained together during deserialization to perform malicious actions. Successful exploitation can lead to complete compromise of the WordPress installation, including database access, file system manipulation, and remote code execution.

The network-accessible attack vector means this vulnerability can be exploited remotely without authentication, significantly increasing its risk profile for internet-facing WordPress sites.

Root Cause

The root cause of CVE-2024-23512 lies in the ProductX plugin's failure to implement proper input validation on serialized data. When the application accepts user-controlled serialized strings and passes them to deserialization functions without sanitization, attackers can craft malicious payloads containing arbitrary PHP objects.

Upon deserialization, PHP automatically instantiates these objects and executes magic methods such as __wakeup(), __destruct(), or __toString(). If these methods or any methods they call can be leveraged to perform sensitive operations, attackers can chain them together to achieve code execution or other malicious outcomes.

Attack Vector

The attack vector for this vulnerability is network-based, allowing remote exploitation without authentication. An attacker would craft a malicious serialized PHP object payload and submit it through a vulnerable endpoint in the ProductX plugin.

The exploitation process typically involves:

1. Identifying a vulnerable input point that accepts serialized data
2. Analyzing available classes in the WordPress installation for exploitable gadget chains
3. Crafting a serialized payload that leverages these gadget chains
4. Submitting the payload to trigger deserialization and execute the malicious chain

For detailed technical information about this vulnerability, see the Patchstack Vulnerability Advisory.

Detection Methods for CVE-2024-23512

Indicators of Compromise

• Unexpected PHP serialized strings in web server access logs, particularly those containing unusual class names or object structures
• Suspicious file modifications or new files appearing in WordPress directories
• Unusual database modifications or new administrator accounts
• Web server error logs showing PHP object instantiation errors or unexpected method calls

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block serialized PHP payloads in HTTP requests
• Implement file integrity monitoring on WordPress core files, plugin directories, and theme files
• Review access logs for requests containing base64-encoded or URL-encoded serialized data patterns (e.g., O: followed by numeric values)
• Monitor for unauthorized administrative actions or plugin modifications

Monitoring Recommendations

• Enable verbose logging on WordPress and web server to capture detailed request information
• Implement real-time alerting for file system changes in plugin directories
• Monitor database for unexpected user account creations or privilege changes
• Deploy endpoint detection solutions capable of identifying PHP-based exploitation attempts

How to Mitigate CVE-2024-23512

Immediate Actions Required

• Update ProductX – WooCommerce Builder & Gutenberg WooCommerce Blocks plugin to a version newer than 3.1.4 immediately
• Review WordPress access logs for any suspicious serialized data submissions
• Audit administrator accounts and remove any unauthorized users
• Scan the WordPress installation for malicious files or backdoors

Patch Information

A security patch addressing this PHP Object Injection vulnerability is available. Site administrators should update the ProductX plugin through the WordPress admin dashboard or by downloading the latest version directly from the WordPress plugin repository. Always verify the integrity of downloaded plugins and perform updates in a staging environment when possible.

For additional details, consult the Patchstack Vulnerability Advisory.

Workarounds

• If immediate patching is not possible, consider temporarily deactivating the ProductX plugin until an update can be applied
• Implement WAF rules to block requests containing PHP serialized object patterns
• Restrict access to WordPress admin and plugin endpoints via IP whitelisting where feasible
• Ensure regular backups are in place to enable rapid recovery in case of compromise

# Configuration example - WAF rule pattern for PHP serialization detection
# Block requests containing PHP serialized object patterns
# ModSecurity rule example:
SecRule REQUEST_BODY "@rx O:\d+:\"[a-zA-Z_]" \
    "id:100001,\
    phase:2,\
    deny,\
    status:403,\
    msg:'Potential PHP Object Injection attempt blocked'"