CVE-2018-17451
📋 TL;DR
This vulnerability allows attackers to perform Cross-Site Request Forgery (CSRF) attacks against GitLab's Slack integration, enabling unauthorized execution of slash commands. It affects GitLab Community and Enterprise Edition users with Slack integration configured. Attackers could manipulate legitimate users into performing unintended actions through crafted requests.
💻 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
Attackers could execute arbitrary slash commands with the victim's permissions, potentially modifying repositories, creating/deleting issues, or performing other administrative actions depending on the user's role.
Likely Case
Attackers trick authenticated users into executing unwanted slash commands, leading to unauthorized repository changes, issue manipulation, or data exposure.
If Mitigated
With proper CSRF protections and user awareness, the risk is limited to isolated incidents with minimal impact.
🎯 Exploit Status
Exploitation requires social engineering to trick authenticated users into visiting malicious pages. No authentication bypass needed if user is already logged into GitLab.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: GitLab 11.1.7, 11.2.4, or 11.3.1
Vendor Advisory: https://about.gitlab.com/releases/2018/10/01/security-release-gitlab-11-dot-3-dot-1-released/
Restart Required: Yes
Instructions:
1. Backup your GitLab instance. 2. Update to GitLab 11.1.7, 11.2.4, or 11.3.1 using your package manager. 3. Restart GitLab services. 4. Verify the update was successful.
🔧 Temporary Workarounds
Disable Slack Integration
allTemporarily disable the Slack integration to eliminate the attack vector until patching is possible.
Navigate to Admin Area > Settings > Integrations > Slack, then disable or remove the integration
Implement CSRF Tokens Manually
allAdd CSRF protection to Slack integration endpoints if custom development is possible.
🧯 If You Can't Patch
- Disable Slack integration completely
- Implement network segmentation to restrict access to GitLab from untrusted networks
🔍 How to Verify
Check if Vulnerable:
Check GitLab version via Admin Area or command line. If version is < 11.1.7, or 11.2.x < 11.2.4, or 11.3.x < 11.3.1, and Slack integration is enabled, the system is vulnerable.Check Version:
sudo gitlab-rake gitlab:env:info | grep 'GitLab version'Verify Fix Applied:
Confirm GitLab version is 11.1.7, 11.2.4, or 11.3.1 or higher. Verify Slack integration functions normally without CSRF warnings.📡 Detection & Monitoring
Log Indicators:
- Unusual slash command patterns from unexpected IP addresses
- Multiple failed CSRF validations in application logs
Network Indicators:
- Unexpected POST requests to /api/v4/integrations/slack/slash_commands endpoints
SIEM Query:
source="gitlab.log" AND "CSRF token authenticity" AND "failed"