CVE-2023-6690 : What You Need to Know

This CVE record for CVE-2023-6690 was published by GitHub_P on December 21, 2023. The vulnerability revolves around a race condition in GitHub Enterprise Server, affecting versions 3.8.0 and above. This allowed an existing admin to maintain permissions on transferred repositories by altering repository permissions during the transfer process.

Understanding CVE-2023-6690

This section delves into the specifics of CVE-2023-6690, shedding light on its impact, technical details, and mitigation strategies.

What is CVE-2023-6690?

CVE-2023-6690 involves a race condition in GitHub Enterprise Server, enabling an existing admin to manipulate repository permissions during transfer, thereby maintaining control over transferred repositories.

The Impact of CVE-2023-6690

The vulnerability, as classified under CAPEC-29 Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions, had a low severity level with a CVSS base score of 3.9. It required high privileges from the attacker and user interaction, affecting the availability, confidentiality, and integrity of the system.

Technical Details of CVE-2023-6690

This section provides a deeper look into the vulnerability, including its description, affected systems and versions, and exploitation mechanism.

Vulnerability Description

The vulnerability in GitHub Enterprise Server allowed admins to maintain permissions on transferred repositories by exploiting a race condition through GraphQL mutation during the transfer process.

Affected Systems and Versions

GitHub Enterprise Server versions 3.8.0 and above were impacted by this vulnerability. The issue was resolved in versions 3.8.12, 3.9.7, 3.10.4, and 3.11.1.

Exploitation Mechanism

An existing admin could leverage the race condition by conducting a GraphQL mutation to alter repository permissions during the repository transfer within the GitHub Enterprise Server environment.

Mitigation and Prevention

To address CVE-2023-6690 and enhance system security, specific steps need to be taken to mitigate the risk and prevent similar vulnerabilities in the future.

Immediate Steps to Take

Ensure that the GitHub Enterprise Server is updated to versions 3.8.12, 3.9.7, 3.10.4, or 3.11.1.
Monitor and restrict admin permissions to prevent unauthorized alterations to repository permissions.

Long-Term Security Practices

Regularly update GitHub Enterprise Server to the latest versions to patch known vulnerabilities.
Implement proper access control measures to limit the impact of potential race conditions and unauthorized actions.

Patching and Updates

GitHub has released patches for GitHub Enterprise Server versions 3.8.12, 3.9.7, 3.10.4, and 3.11.1 to address the race condition vulnerability. It is recommended to promptly apply these patches to secure the environment against potential exploitation.