CVE-2021-39883 : Security Advisory and Response

This CVE article provides details about an improper authorization vulnerability in GitLab versions.

Understanding CVE-2021-39883

This section will delve into the specifics of the vulnerability in GitLab.

What is CVE-2021-39883?

CVE-2021-39883 is an improper authorization vulnerability in GitLab that allows subgroup members to view epics from all parent subgroups.

The Impact of CVE-2021-39883

The vulnerability has a CVSS base score of 4.3, with low confidentiality impact and no integrity impact. The attack complexity is low, affecting systems via a network.

Technical Details of CVE-2021-39883

In this section, we will explore the technical aspects of the CVE.

Vulnerability Description

GitLab EE versions starting from 13.11 before 14.1.7, 14.2 before 14.2.5, and 14.3 before 14.3.1 have improper authorization checks, leading to the issue.

Affected Systems and Versions

Affected Product: GitLab
Vulnerable Versions:
=13.11, <14.1.7

=14.2, <14.2.5

=14.3, <14.3.1

Exploitation Mechanism

The vulnerability allows subgroup members to access epics from all parent subgroups, impacting the confidentiality of the data.

Mitigation and Prevention

In this section, we discuss the steps to mitigate and prevent exploitation of this vulnerability.

Immediate Steps to Take

Upgrade GitLab to version 14.1.7, 14.2.5, or 14.3.1, where the issue is fixed.
Restrict access permissions for subgroup members to prevent unauthorized viewing.

Long-Term Security Practices

Regularly monitor and update access controls within GitLab.
Conduct security audits to identify and fix authorization issues proactively.

Patching and Updates

Stay informed about security patches released by GitLab and apply them promptly.
Keep GitLab software up to date to ensure the latest security enhancements are in place.