CVE-2023-3399 : Exploit Details and Defense Strategies

An improper access control vulnerability has been discovered in GitLab EE, affecting multiple versions. This vulnerability allowed unauthorized project or group members to read the CI/CD variables using custom project templates.

Understanding CVE-2023-3399

This section will cover the details and impact of the CVE-2023-3399 vulnerability in GitLab.

What is CVE-2023-3399?

CVE-2023-3399 is a security vulnerability in GitLab EE that enabled unauthorized project or group members to access and read CI/CD variables utilizing custom project templates.

The Impact of CVE-2023-3399

The impact of this vulnerability is rated as HIGH, with a CVSS base score of 8.5. It could lead to unauthorized disclosure of sensitive information, posing a risk to the confidentiality of data.

Technical Details of CVE-2023-3399

In this section, we will delve into the technical aspects of the CVE-2023-3399 vulnerability.

Vulnerability Description

The vulnerability stemmed from improper access control mechanisms within GitLab EE, allowing unauthorized users to retrieve CI/CD variables through custom project templates.

Affected Systems and Versions

GitLab versions starting from 11.6 before 16.3.6, starting from 16.4 before 16.4.2, and starting from 16.5 before 16.5.1 are affected by this vulnerability.

Exploitation Mechanism

Unauthorized project or group members could exploit this vulnerability to access and read CI/CD variables by leveraging the custom project templates feature.

Mitigation and Prevention

To address CVE-2023-3399 and enhance the security posture of GitLab instances, the following mitigation measures should be implemented:

Immediate Steps to Take

Upgrade to GitLab versions 16.5.1, 16.4.2, 16.3.6, or above to mitigate the vulnerability effectively.

Long-Term Security Practices

Regularly monitor and update access controls to prevent unauthorized access to sensitive data.
Conduct security assessments and audits to identify and address access control vulnerabilities proactively.

Patching and Updates

Stay informed about security patches and updates released by GitLab and promptly apply them to ensure the protection of your GitLab environment.