CVE-2021-20283 : Security Advisory and Response

This article provides an in-depth look at CVE-2021-20283, a vulnerability affecting Moodle versions prior to 3.10.2, 3.9.5, 3.8.8, and 3.5.17.

Understanding CVE-2021-20283

CVE-2021-20283 is a security flaw in Moodle that allowed the web service to fetch other users' enrolled courses without validating the requesting user's permission to view the information in each course.

What is CVE-2021-20283?

The vulnerability in Moodle versions prior to 3.10.2, 3.9.5, 3.8.8, and 3.5.17 allowed unauthorized users to access sensitive information about other users' enrolled courses.

The Impact of CVE-2021-20283

This security flaw could lead to a breach of privacy and confidentiality, exposing course enrollment details of users to unauthorized individuals.

Technical Details of CVE-2021-20283

The vulnerability description, affected systems and versions, and exploitation mechanism are outlined below.

Vulnerability Description

The web service in Moodle did not properly validate the requesting user's permission to view information in enrolled courses, potentially exposing sensitive data.

Affected Systems and Versions

Moodle versions before 3.10.2, 3.9.5, 3.8.8, and 3.5.17 are impacted by this vulnerability.

Exploitation Mechanism

Attackers could exploit this flaw by leveraging the lack of proper permission validation to access sensitive course enrollment information.

Mitigation and Prevention

To address CVE-2021-20283, immediate steps should be taken along with long-term security practices and timely patching and updates.

Immediate Steps to Take

Moodle administrators should update their systems to the latest patched versions to prevent unauthorized access to course enrollment data.

Long-Term Security Practices

Implementing strict access controls and regular security audits can help prevent similar vulnerabilities in the future.

Patching and Updates

Regularly check for security updates and apply patches promptly to mitigate the risk of unauthorized data access.