CVE-2024-47636: Eyecix JobSearch Object Injection Flaw

CVE-2024-47636 Overview

A critical PHP Object Injection vulnerability has been identified in the eyecix JobSearch (wp-jobsearch) WordPress plugin. This insecure deserialization flaw allows unauthenticated attackers to inject arbitrary PHP objects through untrusted data, potentially leading to remote code execution, unauthorized data access, or complete site compromise.

Critical Impact

Unauthenticated attackers can exploit this PHP Object Injection vulnerability to execute arbitrary code, access sensitive data, or completely compromise WordPress installations running vulnerable versions of the JobSearch plugin.

Affected Products

• eyecix JobSearch (wp-jobsearch) plugin versions up to and including 2.5.9
• WordPress installations using the affected plugin versions
• All eyecix jobsearch_wp_job_board deployments prior to the security patch

Discovery Timeline

• 2024-10-10 - CVE-2024-47636 published to NVD
• 2026-04-01 - Last updated in NVD database

Technical Details for CVE-2024-47636

Vulnerability Analysis

This vulnerability stems from improper handling of serialized data within the JobSearch WordPress plugin. PHP Object Injection occurs when user-supplied input is passed to the unserialize() function without proper validation. When a WordPress plugin deserializes untrusted data, attackers can craft malicious serialized objects that, when unserialized, trigger dangerous "magic methods" such as __wakeup(), __destruct(), or __toString().

The vulnerability is classified under CWE-502 (Deserialization of Untrusted Data), which represents one of the most severe vulnerability classes in web applications due to its potential for remote code execution.

Root Cause

The root cause of this vulnerability is the improper validation and sanitization of user-controlled data before it is passed to PHP's deserialization functions. The wp-jobsearch plugin fails to implement secure deserialization practices, allowing attackers to inject crafted serialized PHP objects. When these malicious payloads are processed by the application, they can instantiate arbitrary classes and invoke their magic methods, leading to unintended and dangerous behavior.

Attack Vector

This vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker can craft a malicious HTTP request containing a specially crafted serialized PHP payload. When the vulnerable plugin processes this request and deserializes the malicious input, it triggers the instantiation of attacker-controlled objects. Combined with existing PHP classes that contain exploitable magic methods (often called "gadget chains"), this can lead to arbitrary file operations, SQL injection, or remote code execution.

The attack typically involves:

1. Identifying an entry point where the plugin accepts serialized data
2. Crafting a malicious serialized PHP object payload utilizing available gadget chains
3. Sending the payload to the vulnerable endpoint
4. The plugin deserializes the malicious object, triggering the exploit chain

For detailed technical information about this vulnerability, refer to the Patchstack WordPress Vulnerability Report.

Detection Methods for CVE-2024-47636

Indicators of Compromise

• Unusual serialized data patterns in HTTP request parameters, particularly those containing O: prefixes indicating PHP object serialization
• Unexpected file creation or modification in WordPress directories
• Anomalous database queries or unauthorized data access originating from the wp-jobsearch plugin
• Web server logs showing requests with base64-encoded or URL-encoded serialized PHP objects

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block serialized PHP object patterns in request parameters
• Monitor for known PHP gadget chain signatures in incoming HTTP traffic
• Deploy file integrity monitoring on critical WordPress directories to detect unauthorized modifications
• Configure intrusion detection systems to alert on suspicious deserialization patterns

Monitoring Recommendations

• Enable detailed logging for the wp-jobsearch plugin and review logs for unusual activity
• Monitor WordPress error logs for PHP warnings or errors related to unserialization
• Implement real-time alerting for any file system changes within the WordPress installation
• Track outbound network connections from the web server that could indicate successful exploitation

How to Mitigate CVE-2024-47636

Immediate Actions Required

• Update the eyecix JobSearch (wp-jobsearch) plugin to a patched version immediately
• If an update is not available, deactivate and remove the wp-jobsearch plugin until a security patch is released
• Review WordPress access logs for any signs of exploitation attempts
• Conduct a security audit of the WordPress installation to identify any potential compromise

Patch Information

Organizations using the wp-jobsearch plugin should check the official WordPress plugin repository or contact eyecix directly for the latest security update. Versions through 2.5.9 are confirmed vulnerable. Monitor the Patchstack WordPress Vulnerability Report for patch availability and update information.

Workarounds

• Temporarily disable or uninstall the wp-jobsearch plugin until a patched version is available
• Implement a Web Application Firewall with rules to block serialized PHP object patterns in requests
• Restrict access to the WordPress admin area and plugin endpoints using IP whitelisting
• Consider using PHP runtime security solutions that can detect and block deserialization attacks

# Configuration example - WAF rule to block serialized PHP objects (ModSecurity)
SecRule ARGS "@rx O:[0-9]+:\"" "id:100001,phase:2,deny,status:403,msg:'Potential PHP Object Injection detected'"