CVE-2021-39936 Explained : Impact and Mitigation

This CVE-2021-39936 article provides insights into an improper access control vulnerability affecting GitLab versions.

Understanding CVE-2021-39936

This section delves into the details of the CVE-2021-39936 vulnerability.

What is CVE-2021-39936?

CVE-2021-39936 is an improper access control vulnerability in GitLab CE/EE, impacting versions >=10.7 and <14.3.6, >=14.4 and <14.4.4, >=14.5 and <14.5.2. It enables attackers with a deploy token to access a disabled project wiki.

The Impact of CVE-2021-39936

The vulnerability has a CVSS base score of 3.5 (Low severity) with low confidentiality impact and no integrity impact. It requires network access and user interaction.

Technical Details of CVE-2021-39936

This section provides in-depth technical information about the vulnerability.

Vulnerability Description

The vulnerability involves improper access control in GitLab CE/EE versions, allowing unauthorized access to disabled project wikis.

Affected Systems and Versions

Affected versions include GitLab >=10.7 and <14.3.6, >=14.4 and <14.4.4, >=14.5 and <14.5.2

Exploitation Mechanism

The attacker must obtain a deploy token to exploit the vulnerability and gain access to a project's disabled wiki.

Mitigation and Prevention

Explore the necessary steps to mitigate and prevent potential exploitation of CVE-2021-39936.

Immediate Steps to Take

Update GitLab to versions that have addressed the vulnerability
Monitor project wiki access and deploy tokens

Long-Term Security Practices

Regularly review and update access controls in GitLab
Educate users on secure token management

Patching and Updates

Apply security patches released by GitLab promptly