CVE-2023-4223 : Security Advisory and Response

This CVE-2023-4223 was assigned by STAR Labs and was published on November 28, 2023. It involves an unrestricted file upload vulnerability in Chamilo LMS version 1.11.24 and below, allowing authenticated attackers with a learner role to achieve remote code execution by uploading PHP files.

Understanding CVE-2023-4223

This vulnerability in Chamilo LMS exposes a critical risk as authenticated users could potentially gain unauthenticated remote code execution, leading to severe consequences if exploited maliciously.

What is CVE-2023-4223?

The CVE-2023-4223 vulnerability involves an unrestricted file upload functionality in Chamilo LMS versions 1.11.24 and below, enabling authenticated attackers with a learner role to upload PHP files and execute remote code on the system.

The Impact of CVE-2023-4223

The impact of CVE-2023-4223 is significant, with a high CVSS base score of 8.8, indicating a high severity level. The vulnerability could result in the compromise of confidentiality, integrity, and availability of the system, making it a critical issue to address promptly.

Technical Details of CVE-2023-4223

This section delves into the specific technical details of the CVE-2023-4223 vulnerability, including its description, affected systems and versions, and exploitation mechanism.

Vulnerability Description

The vulnerability arises from the unrestricted file upload capability in

/main/inc/ajax/document.ajax.php

within Chamilo LMS versions 1.11.24 and below. This flaw allows authenticated attackers with a learner role to upload PHP files, thereby executing remote code on the server.

Affected Systems and Versions

Chamilo LMS versions up to and including 1.11.24 are affected by this vulnerability. Users of these versions are at risk of exploitation by attackers with authenticated access and a learner role.

Exploitation Mechanism

To exploit CVE-2023-4223, an authenticated attacker with a learner role can leverage the unrestricted file upload functionality within Chamilo LMS to upload malicious PHP files. Once uploaded, these files can be executed remotely, leading to the compromise of the system.

Mitigation and Prevention

Addressing CVE-2023-4223 promptly is crucial to mitigate the risks associated with this vulnerability. Implementing the following measures can help enhance the security posture of affected systems.

Immediate Steps to Take

Upgrade Chamilo LMS to a patched version above 1.11.24 to eliminate the unrestricted file upload vulnerability.
Educate users on safe file upload practices and restrict file upload permissions to authorized roles only.

Long-Term Security Practices

Conduct regular security assessments and penetration testing to identify and address potential vulnerabilities proactively.
Monitor file upload activities and network traffic to detect any suspicious behavior that could indicate an exploitation attempt.

Patching and Updates

Refer to the provided patches on GitHub to apply the necessary fixes for CVE-2023-4223 and other related vulnerabilities.
Stay informed about security advisories from Chamilo LMS to promptly address any emerging security issues and apply recommended patches.