CVE-2021-39944
📋 TL;DR
This vulnerability allows GitLab users with developer role permissions to elevate their privileges to maintainer level when importing projects. It affects all GitLab Community Edition and Enterprise Edition installations running vulnerable versions. Attackers could gain unauthorized access to sensitive project settings and data.
💻 Affected Systems
- GitLab Community Edition
- GitLab Enterprise Edition
📦 What is this software?
Gitlab by Gitlab
GitLab is a complete DevOps platform providing source code management, CI/CD pipelines, security scanning, container registry, and collaboration tools used by millions of developers and thousands of enterprises worldwide. As both a cloud-hosted SaaS offering (GitLab.com) and self-managed software, G...
Learn more about Gitlab →Gitlab by Gitlab
GitLab is a complete DevOps platform providing source code management, CI/CD pipelines, security scanning, container registry, and collaboration tools used by millions of developers and thousands of enterprises worldwide. As both a cloud-hosted SaaS offering (GitLab.com) and self-managed software, G...
Learn more about Gitlab →Gitlab by Gitlab
GitLab is a complete DevOps platform providing source code management, CI/CD pipelines, security scanning, container registry, and collaboration tools used by millions of developers and thousands of enterprises worldwide. As both a cloud-hosted SaaS offering (GitLab.com) and self-managed software, G...
Learn more about Gitlab →Gitlab by Gitlab
GitLab is a complete DevOps platform providing source code management, CI/CD pipelines, security scanning, container registry, and collaboration tools used by millions of developers and thousands of enterprises worldwide. As both a cloud-hosted SaaS offering (GitLab.com) and self-managed software, G...
Learn more about Gitlab →Gitlab by Gitlab
GitLab is a complete DevOps platform providing source code management, CI/CD pipelines, security scanning, container registry, and collaboration tools used by millions of developers and thousands of enterprises worldwide. As both a cloud-hosted SaaS offering (GitLab.com) and self-managed software, G...
Learn more about Gitlab →Gitlab by Gitlab
GitLab is a complete DevOps platform providing source code management, CI/CD pipelines, security scanning, container registry, and collaboration tools used by millions of developers and thousands of enterprises worldwide. As both a cloud-hosted SaaS offering (GitLab.com) and self-managed software, G...
Learn more about Gitlab →⚠️ Risk & Real-World Impact
Worst Case
Developer role users gain maintainer privileges across imported projects, enabling them to modify project settings, delete repositories, access sensitive data, and potentially compromise the entire GitLab instance through privilege escalation chains.
Likely Case
Malicious or compromised developer accounts gain unauthorized maintainer access to projects they import, allowing them to modify project configurations, access protected branches, and potentially exfiltrate source code or sensitive data.
If Mitigated
With proper role-based access controls and monitoring, impact is limited to specific imported projects, allowing quick detection and remediation of unauthorized privilege changes.
🎯 Exploit Status
Exploitation requires authenticated developer role access. The vulnerability is well-documented in public reports with technical details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 14.3.6, 14.4.4, or 14.5.2
Vendor Advisory: https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39944.json
Restart Required: Yes
Instructions:
1. Backup your GitLab instance. 2. Update to GitLab 14.3.6, 14.4.4, or 14.5.2 depending on your current version track. 3. Restart GitLab services. 4. Verify the update was successful.
🔧 Temporary Workarounds
Restrict Project Import Permissions
linuxTemporarily disable project import functionality for developer role users until patching is complete.
# Edit GitLab configuration to restrict imports
# Set in gitlab.rb: gitlab_rails['gitlab_import_enabled'] = false
# Then run: gitlab-ctl reconfigure
🧯 If You Can't Patch
- Implement strict monitoring of user role changes and project import activities
- Review and audit all developer role users' activities, especially project imports and privilege changes
🔍 How to Verify
Check if Vulnerable:
Check GitLab version with: sudo gitlab-rake gitlab:env:info | grep 'Version:'Check Version:
sudo gitlab-rake gitlab:env:info | grep 'Version:'Verify Fix Applied:
Confirm version is 14.3.6, 14.4.4, or 14.5.2 or higher. Test that developer role users cannot elevate privileges during project import.📡 Detection & Monitoring
Log Indicators:
- Unusual user role changes from developer to maintainer
- Multiple project imports by same developer user
- Audit events showing privilege escalation
Network Indicators:
- Increased API calls to project import endpoints
- Unusual patterns in GitLab API usage
SIEM Query:
source="gitlab" AND (event="user_role_change" OR event="project_import") AND user_role="developer"🔗 References
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39944.json
- https://gitlab.com/gitlab-org/gitlab/-/issues/336531
- https://hackerone.com/reports/1256017
- https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39944.json
- https://gitlab.com/gitlab-org/gitlab/-/issues/336531
- https://hackerone.com/reports/1256017
