CVE-2023-3401 in GitLab
Summary
by MITRE • 08/02/2023
An issue has been discovered in GitLab affecting all versions before 16.0.8, all versions starting from 16.1 before 16.1.3, all versions starting from 16.2 before 16.2.2. The main branch of a repository with a specially designed name allows an attacker to create repositories with malicious code.
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Analysis
by VulDB Data Team • 08/24/2023
This vulnerability in GitLab represents a critical directory traversal and repository creation flaw that enables attackers to exploit specially crafted repository names to gain unauthorized access to repository contents and potentially execute malicious code. The issue affects multiple version ranges including all versions before 16.0.8, versions from 16.1 before 16.1.3, and versions from 16.2 before 16.2.2, indicating a widespread impact across the GitLab ecosystem. The vulnerability stems from inadequate input validation and sanitization of repository names during the creation process, allowing malicious actors to manipulate the system's repository handling mechanisms through carefully constructed naming conventions.
The technical flaw manifests when an attacker creates a repository with a specially designed name that bypasses normal repository creation restrictions and directory traversal protections. This vulnerability operates at the core of GitLab's repository management system, where repository names are not properly sanitized before being processed by the underlying file system operations. The flaw allows attackers to manipulate the repository creation flow to access or create files in unintended locations within the GitLab server's file system, potentially leading to arbitrary code execution or unauthorized data access. This type of vulnerability is classified as a directory traversal attack pattern that aligns with CWE-22, which specifically addresses improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal vulnerabilities.
The operational impact of this vulnerability is severe as it provides attackers with the capability to create repositories containing malicious code that can be executed within the GitLab environment. This creates a significant risk for organizations relying on GitLab for source code management, as attackers can potentially inject harmful code into repositories or access sensitive data from other repositories. The vulnerability particularly affects the main branch handling mechanism, allowing attackers to manipulate repository structures and potentially gain access to privileged operations. This type of attack vector is particularly dangerous in enterprise environments where GitLab serves as a central code repository and collaboration platform, as it could lead to supply chain attacks or unauthorized access to confidential source code and development artifacts.
Organizations should immediately upgrade to GitLab versions 16.0.8, 16.1.3, or 16.2.2 to remediate this vulnerability, as these releases contain the necessary patches to address the repository name validation issues. The mitigation strategy should also include implementing additional security controls such as repository name validation policies, monitoring for suspicious repository creation patterns, and restricting repository creation privileges to authorized users only. Security teams should conduct thorough audits of existing repositories to identify any potential exploitation attempts and implement network-level monitoring to detect unusual repository creation activities. This vulnerability demonstrates the importance of proper input validation and sanitization in web applications, aligning with ATT&CK technique T1059.006 for execution through command and script interpreters, as the malicious code execution occurs through the repository creation and manipulation process. The security community should also consider implementing automated scanning tools to detect potentially malicious repository names and establish incident response procedures specifically addressing repository manipulation attacks.