CVE-2019-14879 : Exploit Details and Defense Strategies

A security loophole has been discovered in Moodle versions 3.7.x prior to 3.7.3, 3.6.x prior to 3.6.7, and 3.5.x prior to 3.5.9. When a cohort role assignment was removed, the related capabilities were not being revoked as they should have been.

Understanding CVE-2019-14879

This CVE involves a vulnerability in Moodle versions that could lead to unauthorized access due to improper revocation of capabilities.

What is CVE-2019-14879?

CVE-2019-14879 is a security vulnerability found in Moodle versions 3.5.x, 3.6.x, and 3.7.x, where removing a cohort role assignment fails to revoke associated capabilities, potentially leading to unauthorized access.

The Impact of CVE-2019-14879

The vulnerability has a CVSS base score of 4.2, indicating a medium severity issue with low confidentiality and integrity impacts. The attack complexity is high, but no user interaction is required.

Technical Details of CVE-2019-14879

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The issue arises when removing cohort role assignments in Moodle versions 3.5.x, 3.6.x, and 3.7.x, resulting in the failure to revoke associated capabilities, potentially allowing unauthorized access.

Affected Systems and Versions

Affected Versions: Moodle 3.7.x before 3.7.3, 3.6.x before 3.6.7, 3.5.x before 3.5.9
Vendor: Moodle (Vendor details unknown)

Exploitation Mechanism

The vulnerability can be exploited by an attacker who has access to remove cohort role assignments, allowing them to retain capabilities that should have been revoked.

Mitigation and Prevention

To address CVE-2019-14879 and enhance system security, follow these mitigation steps:

Immediate Steps to Take

Upgrade Moodle to the patched versions (3.7.3, 3.6.7, 3.5.9) to mitigate the vulnerability.
Regularly review and update role assignments to ensure proper access control.

Long-Term Security Practices

Conduct regular security audits to identify and address vulnerabilities promptly.
Educate users on proper role assignment and access control practices.

Patching and Updates

Stay informed about security updates and patches released by Moodle to address vulnerabilities like CVE-2019-14879.