CodeIgniter4, the 4.x branch of the popular PHP full-stack web framework CodeIgniter, has been reported to contain an improper input validation vulnerability prior to version 4.1.9. This security flaw allows attackers to execute CLI (Command Line Interface) routes via HTTP (HyperText Transfer Protocol) requests, which could have serious consequences in terms of data confidentiality, integrity, and system availability. Fortunately, this vulnerability has been patched in version 4.1.9, and there are currently no known workarounds other than updating to the patched version.

Exploit Details

The improper input validation vulnerability is located in the CodeIgniter4 framework's Source Code, specifically in the system/CLI/CommandRunner.php file. This file contains a method named 'run()', which is responsible for executing CLI commands. Due to the improper input validation, the 'run()' method can be exploited by malicious actors to execute CLI routes via HTTP requests, by passing in an altered 'argv' array.

Here's a code snippet showcasing the vulnerable section in CommandRunner.php

public function run(array $params)
{
    // ...

    $command = array_shift($params);

    // ...

    $this->caller->call('App\Commands\\' . $command, $params);

    // ...
}

A potential attack scenario could involve an attacker sending a carefully crafted HTTP request that leverages the improper input validation vulnerability. The request would contain an 'argv' array with the attacker's malicious CLI command, which when executed by the 'run()' method, could lead to unauthorized access, data exfiltration, or even system takeover.

Patch Information and References

Thankfully, the CodeIgniter4 development team addressed this vulnerability in version 4.1.9. The patch introduces stricter input validation mechanisms, ensuring that only legitimate CLI commands from authorized sources can be executed. Users are urged to update their CodeIgniter4 installations to version 4.1.9 or newer to protect against the exploit.

Refer to the official CodeIgniter4 GitHub repository for the patch details

- CodeIgniter4 4.1.9 Release

In addition, the following resources provide more information about the vulnerability

- CVE-2022-24711 – The CVE entry with a description of the security vulnerability
- CodeIgniter4 Security Advisory – Official security advisories and recommendations from the CodeIgniter4 development team

Conclusion

It is crucial for developers using the CodeIgniter4 PHP full-stack web framework to be aware of this vulnerability and act promptly to mitigate it. By updating to the patched version 4.1.9 or newer, affected installations can be safeguarded against potential exploitation by malicious actors. Developers should always be vigilant and stay updated on security issues, as well as ensure that their web applications follow the latest best practices in terms of secure coding and deployment.

Timeline

Published on: 02/28/2022 16:15:00 UTC
Last modified on: 03/08/2022 18:03:00 UTC