CVE-2024-49688: ARPrice Object Injection Vulnerability

CVE-2024-49688 Overview

CVE-2024-49688 is an Insecure Deserialization vulnerability affecting the ARPrice WordPress plugin developed by ReputeInfoSystems. This vulnerability allows attackers to perform PHP Object Injection attacks by exploiting improper handling of serialized data. The flaw exists in versions up to and including 4.1.3 of the ARPrice plugin.

PHP Object Injection vulnerabilities occur when user-controllable data is passed to PHP's unserialize() function without proper validation. When combined with available "gadget chains" within the application or its dependencies, attackers can achieve various malicious outcomes including remote code execution, file manipulation, or privilege escalation.

Critical Impact

Unauthenticated attackers may exploit this PHP Object Injection vulnerability to execute arbitrary code, manipulate files, or compromise the WordPress installation entirely depending on available POP (Property Oriented Programming) chains.

Affected Products

• ARPrice WordPress Plugin versions through 4.1.3
• WordPress installations using vulnerable ARPrice plugin versions
• Websites with the arprice plugin installed and active

Discovery Timeline

• 2025-01-21 - CVE-2024-49688 published to NVD
• 2026-04-01 - Last updated in NVD database

Technical Details for CVE-2024-49688

Vulnerability Analysis

This vulnerability is classified under CWE-502 (Deserialization of Untrusted Data). The ARPrice plugin fails to properly sanitize or validate serialized data before passing it to PHP's deserialization functions. This architectural flaw allows attackers to inject malicious serialized objects that, when deserialized, can trigger unintended code paths within the application.

The unauthenticated nature of this vulnerability significantly increases its severity, as no prior authentication is required to exploit it. Attackers can craft malicious payloads targeting specific classes available within WordPress core, the ARPrice plugin itself, or any other installed plugins and themes that contain exploitable magic methods (__wakeup, __destruct, __toString, etc.).

Root Cause

The root cause of this vulnerability lies in the unsafe use of PHP's unserialize() function on user-controllable input. The ARPrice plugin does not implement proper input validation, whitelisting of allowed classes, or use of safer serialization formats like JSON. When serialized data from an untrusted source is deserialized, PHP automatically instantiates objects and calls magic methods, enabling attackers to chain method calls and achieve malicious outcomes.

Attack Vector

The attack vector for this vulnerability involves sending specially crafted serialized PHP objects to the vulnerable endpoint. An attacker would:

1. Identify exploitable endpoints in the ARPrice plugin that process serialized data
2. Analyze available classes (gadgets) in WordPress, ARPrice, and other plugins for exploitable magic methods
3. Construct a POP chain that achieves the desired malicious action
4. Serialize the malicious object and send it to the vulnerable endpoint
5. Upon deserialization, the injected objects execute the attacker's payload

Since this is an unauthenticated vulnerability, attackers can exploit it without any prior access to the WordPress installation.

Detection Methods for CVE-2024-49688

Indicators of Compromise

• Unusual serialized data patterns in web server access logs, particularly containing PHP object notation (O: followed by class names)
• Unexpected file modifications or new files appearing in WordPress directories
• Anomalous outbound connections from the web server
• WordPress database modifications not attributable to legitimate user activity

Detection Strategies

• Monitor web application firewall (WAF) logs for serialized PHP object patterns in request parameters
• Implement file integrity monitoring on WordPress core files, plugins, and themes
• Review access logs for suspicious POST requests targeting ARPrice plugin endpoints
• Deploy intrusion detection rules to identify serialization attack patterns

Monitoring Recommendations

• Enable detailed logging for the ARPrice plugin and WordPress core
• Configure alerts for any attempts to access deprecated or unusual plugin endpoints
• Monitor for execution of system commands or shell spawning from web server processes
• Implement real-time log analysis to detect serialized object injection attempts

How to Mitigate CVE-2024-49688

Immediate Actions Required

• Update the ARPrice plugin to a patched version immediately when available
• If no patch is available, consider temporarily disabling or removing the ARPrice plugin
• Implement WAF rules to block requests containing serialized PHP objects
• Audit WordPress installation for signs of compromise

Patch Information

Organizations should monitor the Patchstack WordPress Vulnerability Report for updates on patch availability. Contact ReputeInfoSystems directly for information about security updates for the ARPrice plugin. Ensure WordPress core and all other plugins are updated to their latest versions to reduce the available attack surface for POP chain exploitation.

Workarounds

• Disable the ARPrice plugin until a patch is available
• Implement strict input validation at the WAF level to block serialized data in requests
• Restrict access to WordPress admin and plugin endpoints using IP whitelisting where possible
• Consider implementing a virtual patching solution to filter malicious serialization attempts

# Example: Block serialized PHP objects in Apache .htaccess
# Add to .htaccess in WordPress root directory
<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{QUERY_STRING} (O:[0-9]+:) [NC,OR]
    RewriteCond %{REQUEST_BODY} (O:[0-9]+:) [NC]
    RewriteRule .* - [F,L]
</IfModule>