CVE-2021-39868 : Security Advisory and Response

In this article, we will explore the details of CVE-2021-39868, a vulnerability in GitLab that allows an authenticated low-privileged user to manipulate project exports.

Understanding CVE-2021-39868

CVE-2021-39868 is a vulnerability in GitLab that affects versions 8.12 to 14.3.1. An attacker can exploit this issue to create a project with an unlimited repository size.

What is CVE-2021-39868?

CVE-2021-39868 is a security vulnerability in GitLab that enables a low-privileged authenticated user to manipulate project exports, potentially leading to creating projects with unlimited repository size.

The Impact of CVE-2021-39868

The impact of this vulnerability is rated as medium with a base score of 4.3. The attacker can perform unauthorized actions by exploiting this issue.

Technical Details of CVE-2021-39868

CVE-2021-39868 involves the following technical aspects:

Vulnerability Description

The vulnerability arises from improper input validation in GitLab, allowing malicious users to create projects with unlimited repository size.

Affected Systems and Versions

Affected Product: GitLab
Vulnerable Versions: >=8.12, <14.1.7, >=14.2, <14.2.5, >=14.3, <14.3.1

Exploitation Mechanism

The attacker, with low privileges, can exploit the vulnerability by modifying values in a project export.

Mitigation and Prevention

To address CVE-2021-39868, consider the following:

Immediate Steps to Take

Update GitLab to a fixed version that addresses the vulnerability.
Monitor project exports for unusual behavior.

Long-Term Security Practices

Regularly review and update access levels for users.
Conduct security training for users on handling project exports securely.

Patching and Updates

Stay informed about security updates from GitLab.
Apply patches promptly to mitigate the risk of exploitation.