CVE-2025-22526: PHP/MySQL CPU Stats Object Injection Flaw

CVE-2025-22526 Overview

CVE-2025-22526 is a critical insecure deserialization vulnerability affecting the PHP/MySQL CPU performance statistics WordPress plugin through version 1.2.1. This vulnerability allows attackers to perform PHP Object Injection attacks by exploiting the deserialization of untrusted data, potentially leading to remote code execution, data manipulation, or complete system compromise.

Critical Impact

Unauthenticated attackers can exploit this vulnerability remotely to inject malicious serialized PHP objects, potentially achieving arbitrary code execution on affected WordPress installations.

Affected Products

• PHP/MySQL CPU performance statistics WordPress Plugin (from n/a through 1.2.1)
• WordPress installations running the vulnerable plugin versions

Discovery Timeline

• March 28, 2025 - CVE-2025-22526 published to NVD
• March 28, 2025 - Last updated in NVD database

Technical Details for CVE-2025-22526

Vulnerability Analysis

This vulnerability stems from CWE-502 (Deserialization of Untrusted Data), a well-known class of security flaws that occurs when applications deserialize user-supplied data without proper validation. In the context of this WordPress plugin, the PHP unserialize() function is used on data that can be influenced by external attackers.

PHP Object Injection vulnerabilities are particularly dangerous because they allow attackers to instantiate arbitrary PHP classes and invoke magic methods such as __wakeup(), __destruct(), or __toString(). When combined with existing classes in the WordPress ecosystem that contain exploitable magic methods (known as "gadget chains"), attackers can achieve remote code execution.

The vulnerability is network-accessible and requires no authentication or user interaction to exploit, making it particularly severe in internet-facing WordPress installations.

Root Cause

The root cause of CVE-2025-22526 is the improper handling of serialized PHP data within the PHP/MySQL CPU performance statistics plugin. The application deserializes user-controllable input without validating that the data originates from a trusted source or contains only expected object types.

In PHP applications, the unserialize() function reconstructs PHP values from serialized string representations. When called on attacker-controlled data, malicious serialized objects can be injected that trigger dangerous operations when their magic methods are invoked during the deserialization process or object destruction.

Attack Vector

The attack vector is network-based, allowing remote exploitation without requiring authentication. An attacker can craft a malicious serialized PHP payload containing objects designed to exploit existing class definitions in the WordPress environment.

The exploitation process typically involves:

1. Identifying an entry point where serialized data is processed by the vulnerable plugin
2. Crafting a serialized payload containing objects that chain together to achieve code execution
3. Sending the malicious payload to the vulnerable endpoint
4. The server deserializes the payload, instantiating the attacker's objects and executing arbitrary code through magic method invocations

For detailed technical information about this vulnerability, refer to the Patchstack security advisory.

Detection Methods for CVE-2025-22526

Indicators of Compromise

• Suspicious HTTP requests containing serialized PHP data patterns (e.g., O:, a:, s: prefixes in parameters)
• Unexpected file creations or modifications in WordPress directories
• Unusual process spawning from PHP or web server processes
• Web server logs showing POST requests with base64-encoded or URL-encoded serialized payloads
• Creation of new administrator accounts or unauthorized privilege changes

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block serialized PHP object patterns in request parameters
• Monitor web server access logs for suspicious payloads containing PHP serialization signatures
• Deploy endpoint detection solutions to identify post-exploitation activities such as webshell creation
• Use file integrity monitoring on WordPress plugin directories to detect unauthorized modifications
• Implement behavioral analysis to detect anomalous PHP process activity

Monitoring Recommendations

• Enable verbose logging on WordPress installations and review for exploitation attempts
• Configure alerting for new user account creation or privilege escalation events
• Monitor outbound network connections from web servers for potential command-and-control activity
• Implement real-time log analysis to correlate suspicious request patterns across multiple endpoints

How to Mitigate CVE-2025-22526

Immediate Actions Required

• Identify all WordPress installations running the PHP/MySQL CPU performance statistics plugin
• Disable or remove the vulnerable plugin immediately until a patched version is available
• Review web server logs for signs of exploitation attempts
• Conduct forensic analysis on potentially compromised systems
• Consider implementing additional WAF rules to block PHP serialization payloads

Patch Information

As of the publication date, users should check with the plugin developer or the Patchstack advisory for updates regarding available patches. The vulnerability affects all versions through 1.2.1. Users should update to a patched version as soon as one becomes available.

Workarounds

• Completely disable or uninstall the PHP/MySQL CPU performance statistics plugin until a security patch is released
• Implement WAF rules to filter requests containing PHP serialized object patterns
• Restrict access to the WordPress admin area and plugin endpoints using IP whitelisting
• Deploy a virtual patching solution through your security platform to block exploitation attempts
• Consider using alternative performance monitoring solutions that do not have known vulnerabilities

# WordPress CLI commands to disable the vulnerable plugin
wp plugin deactivate mywebtonet-performancestats --path=/var/www/html/wordpress

# Remove the plugin entirely if not needed
wp plugin uninstall mywebtonet-performancestats --path=/var/www/html/wordpress

# List all active plugins to verify removal
wp plugin list --status=active --path=/var/www/html/wordpress