CVE-2021-31933 : Security Advisory and Response

A remote code execution vulnerability exists in Chamilo through 1.11.14, allowing a remote attacker to upload a file containing arbitrary PHP code to achieve PHP code execution.

Understanding CVE-2021-31933

This CVE describes a critical remote code execution vulnerability in Chamilo LMS.

What is CVE-2021-31933?

CVE-2021-31933 is a security flaw in Chamilo LMS that allows a remote authenticated administrator to upload a malicious file with PHP code, leading to code execution.

The Impact of CVE-2021-31933

The vulnerability has a high severity impact on confidentiality, integrity, and availability, with a CVSS base score of 7.2.

Technical Details of CVE-2021-31933

The vulnerability arises due to improper input sanitization and file-extension filtering for certain filenames during file uploads.

Vulnerability Description

The flaw enables an authenticated attacker to upload a file with arbitrary PHP code via directory traversal in fileUpload.lib.php.

Affected Systems and Versions

Chamilo versions up to 1.11.14 are vulnerable to this remote code execution issue.

Exploitation Mechanism

A remote authenticated attacker can exploit this vulnerability to execute arbitrary PHP code on the target system.

Mitigation and Prevention

It's crucial to take immediate steps to secure systems and prevent exploitation of this vulnerability.

Immediate Steps to Take

Administrators are advised to restrict file uploads, apply relevant patches, and monitor uploads for malicious content.

Long-Term Security Practices

Regularly update and patch Chamilo LMS, implement proper input validation mechanisms, and monitor for unauthorized file uploads.

Patching and Updates

Refer to the official Chamilo security advisories and apply the latest patches to mitigate the risk of remote code execution.