CVE-2023-3915 : What You Need to Know

An issue has been discovered in GitLab EE that affects multiple versions, allowing external users to escalate their privileges and potentially access internal projects. This vulnerability, assigned by GitLab, has a CVSS base score of 6.5, indicating a medium severity level.

Understanding CVE-2023-3915

This CVE impacts GitLab EE versions starting from 16.1 before 16.1.5, versions starting from 16.2 before 16.2.5, and versions starting from 16.3 before 16.3.1. It involves incorrect execution-assigned permissions, potentially leading to privilege escalation for external users.

What is CVE-2023-3915?

The vulnerability in GitLab EE allows external users with an owner role in a group to create a service account within that group. This service account, classified as internal, can then be misused to access internal projects, resulting in unauthorized access and potential data breaches.

The Impact of CVE-2023-3915

The impact of this vulnerability lies in the ability of external users to elevate their privileges on the GitLab instance, posing a risk to the confidentiality and integrity of internal projects. If exploited, it could lead to unauthorized access and potential data manipulation.

Technical Details of CVE-2023-3915

This vulnerability, categorized under CWE-279 (Incorrect Execution-Assigned Permissions), affects GitLab EE versions 16.1, 16.2, and 16.3, with specific version ranges identified as vulnerable. The CVSS v3.1 base score is 6.5, indicating a medium severity level.

Vulnerability Description

The vulnerability allows external users with an owner role in a group to create a service account, granting them unauthorized access to internal projects within the GitLab instance.

Affected Systems and Versions

GitLab EE versions 16.1, 16.2, and 16.3 are affected by this vulnerability, specifically versions prior to 16.1.5, 16.2.5, and 16.3.1, respectively.

Exploitation Mechanism

By leveraging the owner role in a group, external users can create a service account that bypasses external classification, providing access to internal projects and potentially sensitive data.

Mitigation and Prevention

To address CVE-2023-3915, GitLab recommends taking immediate steps to mitigate the risk and prevent potential exploitation by malicious actors.

Immediate Steps to Take

Users are advised to upgrade their GitLab EE installations to versions 16.1.5, 16.2.5, 16.3.1, or higher to patch the vulnerability and prevent unauthorized privilege escalation.

Long-Term Security Practices

Implementing strong access controls, regularly reviewing user permissions, and monitoring for unusual activities can help enhance overall security posture and prevent similar vulnerabilities in the future.

Patching and Updates

Regularly applying software updates, security patches, and staying informed about security advisories from GitLab are essential practices to protect against known vulnerabilities and ensure system security.