CVE-2023-23766 Explained : Impact and Mitigation

This CVE record pertains to an incorrect comparison vulnerability identified in GitHub Enterprise Server, potentially leading to commit smuggling. The vulnerability was reported via the GitHub Bug Bounty program and affects multiple versions of the GitHub Enterprise Server.

Understanding CVE-2023-23766

This section delves into the details and impact of the CVE-2023-23766 vulnerability in GitHub Enterprise Server.

What is CVE-2023-23766?

The CVE-2023-23766 vulnerability is an incorrect comparison flaw in GitHub Enterprise Server that could be exploited by an attacker with write access to the repository. This vulnerability allowed for commit smuggling by displaying an incorrect diff in a re-opened Pull Request.

The Impact of CVE-2023-23766

The impact of CVE-2023-23766 is categorized under CWE-697, specifically denoting an "Incorrect Comparison" scenario. This vulnerability can lead to high integrity impact, requiring high privileges, while the attack complexity is considered low with required user interaction.

Technical Details of CVE-2023-23766

In this section, we'll explore the vulnerability description, affected systems and versions, as well as the exploitation mechanism related to CVE-2023-23766.

Vulnerability Description

The vulnerability in GitHub Enterprise Server allowed commit smuggling through an incorrect diff display in re-opened Pull Requests, requiring an attacker to possess write access to the repository.

Affected Systems and Versions

GitHub Enterprise Server versions 3.6.0, 3.7.0, 3.8.0, 3.9.0, and 3.10.0 are affected by this vulnerability, with fixed versions being 3.6.17, 3.7.15, 3.8.8, 3.9.3, and 3.10.1.

Exploitation Mechanism

To exploit CVE-2023-23766, an attacker needs to have write access to the affected GitHub Enterprise Server repository, allowing them to manipulate the incorrect comparison vulnerability and potentially engage in commit smuggling.

Mitigation and Prevention

This section outlines the steps to mitigate and prevent the impacts of CVE-2023-23766 within the GitHub Enterprise Server environment.

Immediate Steps to Take

Users should update their GitHub Enterprise Server instances to the fixed versions (3.6.17, 3.7.15, 3.8.8, 3.9.3, or 3.10.1) to address the vulnerability and prevent potential commit smuggling attacks.

Long-Term Security Practices

Maintaining strict access controls and monitoring write access to repository activities can further enhance the security posture against commit smuggling vulnerabilities like the one identified in CVE-2023-23766.

Patching and Updates

Regularly applying security patches and updates released by GitHub for the Enterprise Server can help in staying protected against known vulnerabilities and enhancing overall security resilience.