CVE-2023-22381 Explained : Impact and Mitigation

This CVE involves a code injection vulnerability found in GitHub Enterprise Server, allowing the setting of arbitrary environment variables from a single environment variable value in GitHub Actions when utilizing a Windows-based runner. The vulnerability impacts all versions of GitHub Enterprise Server prior to version 3.8.0 and was addressed in versions 3.4.15, 3.5.12, 3.6.8, and 3.7.5.

Understanding CVE-2023-22381

This section delves into the details of CVE-2023-22381, including its nature and impact.

What is CVE-2023-22381?

CVE-2023-22381 is a code injection vulnerability in GitHub Enterprise Server that allows attackers to manipulate user-controlled variables, potentially leading to unauthorized access or malicious activities.

The Impact of CVE-2023-22381

The vulnerability has a medium severity level, with a base score of 4.1 based on CVSS v3.1 metrics. It requires a high level of privileges for exploitation and could result in attackers gaining control over environment variables used in GitHub Actions.

Technical Details of CVE-2023-22381

This section provides more insight into the vulnerability, its affected systems, versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability in GitHub Enterprise Server permits the injection of arbitrary environment variables via a single environment variable in GitHub Actions, particularly when employing a Windows-based runner.

Affected Systems and Versions

GitHub Enterprise Server versions prior to 3.8.0 are susceptible to this code injection vulnerability. Versions 3.4.15, 3.5.12, 3.6.8, and 3.7.5 have been identified as affected and have been fixed to address this security issue.

Exploitation Mechanism

Exploiting this vulnerability requires existing permissions to manipulate the value of environment variables in GitHub Actions, potentially leading to unauthorized actions within the platform.

Mitigation and Prevention

This section outlines the necessary steps to mitigate and prevent exploitation of CVE-2023-22381.

Immediate Steps to Take

To safeguard against potential exploitation, users are advised to update their GitHub Enterprise Server to version 3.8.0 or later to eliminate the code injection vulnerability and secure environment variable settings in GitHub Actions.

Long-Term Security Practices

Incorporating robust access control measures and regular security assessments can help in identifying and addressing vulnerabilities proactively, enhancing the overall security posture of GitHub Enterprise Server deployments.

Patching and Updates

Regularly applying software updates and patches provided by GitHub for GitHub Enterprise Server is crucial to stay protected against emerging security threats, ensuring a secure and reliable operational environment.