CVE-2023-3979 : Exploit Details and Defense Strategies

This CVE record was published by GitLab on September 29, 2023, after being reserved on July 27, 2023. It addresses the issue of exposure of sensitive information to an unauthorized actor in GitLab.

Understanding CVE-2023-3979

This vulnerability in GitLab impacts versions ranging from 10.6 to 16.4.1. It allows upstream members to collaborate on a branch and potentially gain permission to write to the merge request's source branch.

What is CVE-2023-3979?

CVE-2023-3979 is classified as CWE-200, which involves the exposure of sensitive information to an unauthorized actor. This vulnerability could lead to a breach of confidentiality and integrity in the affected systems.

The Impact of CVE-2023-3979

The impact of this vulnerability is rated as low severity with a CVSS base score of 3.1. It has a low integrity impact and does not affect availability. However, the exposure of sensitive information could lead to unauthorized access and potential data breaches.

Technical Details of CVE-2023-3979

This vulnerability allows unauthorized actors to access and write to the merge request's source branch in GitLab, potentially compromising sensitive information.

Vulnerability Description

The vulnerability arises from a flaw in GitLab that allows upstream members to collaborate on a branch and gain unauthorized writing permissions, compromising the security of the merge request's source branch.

Affected Systems and Versions

All GitLab versions from 10.6 to 16.4.1 are impacted by this vulnerability. Specifically, versions 16.2.8, 16.3.5, and 16.4.1 are affected, with earlier versions being vulnerable to the exposure of sensitive information to unauthorized actors.

Exploitation Mechanism

Exploiting this vulnerability requires collaboration access on a branch in GitLab, enabling unauthorized users to write to the source branch of a merge request and potentially access sensitive information.

Mitigation and Prevention

To address CVE-2023-3979 and mitigate the risk associated with this vulnerability, immediate actions and long-term security practices are recommended.

Immediate Steps to Take

Upgrade GitLab to the latest version, specifically versions 16.4.1, 16.3.5, or 16.2.8, to eliminate the vulnerability and prevent unauthorized access to sensitive information.

Long-Term Security Practices

Implement access controls and permissions in GitLab to restrict collaboration privileges and prevent unauthorized users from writing to sensitive branches.
Regularly monitor and audit user activities to detect any unauthorized access attempts or suspicious behavior within the GitLab environment.

Patching and Updates

Stay informed about security updates and patches released by GitLab to address vulnerabilities and ensure the continuous protection of sensitive information and data integrity within the platform.