CVE-2018-25270: ThinkPHP 5.0.23 RCE Vulnerability

CVE-2018-25270 Overview

ThinkPHP 5.0.23 contains a remote code execution vulnerability that allows unauthenticated attackers to execute arbitrary PHP code by invoking functions through the routing parameter. Attackers can craft requests to the index.php endpoint with malicious function parameters to execute system commands with application privileges.

Critical Impact

This vulnerability enables unauthenticated remote code execution, allowing attackers to fully compromise web applications running ThinkPHP 5.0.23 and execute arbitrary system commands with the privileges of the web server process.

Affected Products

• ThinkPHP 5.0.23

Discovery Timeline

• April 22, 2026 - CVE-2018-25270 published to NVD
• April 22, 2026 - Last updated in NVD database

Technical Details for CVE-2018-25270

Vulnerability Analysis

This remote code execution vulnerability in ThinkPHP 5.0.23 stems from improper handling of routing parameters within the framework. The vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key), indicating that the framework fails to properly validate and restrict function invocations through user-supplied input.

The vulnerability is network-accessible, requiring no authentication or user interaction to exploit. Attackers can leverage this flaw to invoke arbitrary PHP functions, including those capable of executing system commands, through specially crafted HTTP requests to the index.php endpoint.

Root Cause

The root cause of this vulnerability lies in ThinkPHP's routing mechanism, which improperly processes the invokefunction controller action. The framework fails to adequately validate function parameters before execution, allowing attackers to specify arbitrary PHP functions and their arguments through URL parameters. This design flaw enables direct invocation of dangerous functions such as call_user_func_array() without proper authorization checks or input sanitization.

Attack Vector

The attack vector exploits ThinkPHP's URL routing system through the index.php endpoint. Attackers craft malicious HTTP GET requests containing parameters that specify a target function and its arguments. By manipulating the s parameter or similar routing variables, attackers can invoke PHP functions like system(), exec(), or passthru() to execute arbitrary system commands.

The exploitation requires no authentication, making any publicly accessible ThinkPHP 5.0.23 application a potential target. Successful exploitation grants attackers the ability to execute commands with the privileges of the web server user, potentially leading to complete server compromise, data exfiltration, or lateral movement within the network.

For detailed technical information and proof-of-concept examples, refer to the Exploit-DB #45978 entry and the VulnCheck Advisory on ThinkPHP.

Detection Methods for CVE-2018-25270

Indicators of Compromise

• HTTP requests to index.php containing invokefunction or similar function invocation parameters in the URL
• Web server logs showing requests with call_user_func_array, system, exec, passthru, or shell_exec in query strings
• Unusual processes spawned by the web server process (e.g., www-data or apache user)
• Evidence of reconnaissance commands such as whoami, id, or uname in web access logs

Detection Strategies

• Deploy web application firewall (WAF) rules to block requests containing known exploitation patterns for ThinkPHP RCE
• Implement intrusion detection signatures to identify HTTP requests with function invocation parameters targeting index.php
• Monitor web server logs for anomalous query string patterns including PHP function names
• Use endpoint detection and response (EDR) solutions to identify suspicious process chains originating from web server processes

Monitoring Recommendations

• Enable detailed access logging on web servers hosting ThinkPHP applications to capture full query strings
• Configure alerts for HTTP requests containing suspicious parameters such as function=, call_user_func, or command execution functions
• Monitor for unexpected outbound network connections from web server processes that may indicate reverse shells
• Implement file integrity monitoring on ThinkPHP application directories to detect unauthorized modifications

How to Mitigate CVE-2018-25270

Immediate Actions Required

• Immediately upgrade ThinkPHP to a patched version that addresses this vulnerability
• If immediate upgrade is not possible, take vulnerable applications offline or restrict network access
• Review web server logs for evidence of exploitation attempts
• Conduct a thorough security assessment of systems running ThinkPHP 5.0.23 for signs of compromise

Patch Information

Organizations should upgrade to a patched version of ThinkPHP that addresses this remote code execution vulnerability. Consult the GitHub Project Repository and ThinkPHP Official Site for the latest security updates and patched versions. Before deploying patches to production, test thoroughly in a staging environment to ensure application compatibility.

Workarounds

• Deploy a web application firewall (WAF) with rules specifically designed to block ThinkPHP RCE exploitation patterns
• Restrict access to the ThinkPHP application to trusted IP addresses only using network-level controls
• Disable or remove unnecessary controllers and actions that may expose the invokefunction functionality
• Implement strict input validation at the web server or reverse proxy level to filter dangerous query parameters

# Example: Block suspicious requests at the web server level (Nginx)
# Add to server block configuration
location ~ index\.php {
    # Block requests containing dangerous function names
    if ($query_string ~* "(call_user_func|invokefunction|system|exec|passthru)") {
        return 403;
    }
    # Continue with normal PHP processing
    fastcgi_pass unix:/var/run/php/php-fpm.sock;
    include fastcgi_params;
}