CVE-2024-2651
📋 TL;DR
This vulnerability allows attackers to cause denial of service (DoS) in GitLab instances by submitting maliciously crafted markdown content. All GitLab CE/EE instances running vulnerable versions are affected, potentially disrupting service availability.
💻 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
Complete service unavailability of GitLab instance, preventing all users from accessing repositories, CI/CD pipelines, and other GitLab functionality.
Likely Case
Partial service degradation or temporary unavailability affecting specific features that process markdown content.
If Mitigated
Minimal impact with proper input validation and rate limiting in place, though some service disruption may still occur.
🎯 Exploit Status
Exploitation requires ability to submit markdown content (e.g., through issues, comments, or repository content). Attackers need some level of access to the GitLab instance.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 16.9.7, 16.10.5, or 16.11.2
Vendor Advisory: https://gitlab.com/gitlab-org/gitlab/-/issues/450830
Restart Required: Yes
Instructions:
1. Backup your GitLab instance. 2. Update to GitLab 16.9.7, 16.10.5, or 16.11.2 using your preferred update method. 3. Restart GitLab services. 4. Verify the update was successful.
🔧 Temporary Workarounds
Restrict Markdown Input
allLimit who can submit markdown content through GitLab features
Rate Limit Markdown Processing
allImplement rate limiting on endpoints that process markdown
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all markdown content
- Monitor for unusual markdown processing activity and implement alerting
🔍 How to Verify
Check if Vulnerable:
Check GitLab version via Admin Area or command line. If version is before 16.9.7, between 16.10.0-16.10.4, or between 16.11.0-16.11.1, you are vulnerable.Check Version:
sudo gitlab-rake gitlab:env:info | grep 'GitLab Version'Verify Fix Applied:
After patching, verify GitLab version is 16.9.7, 16.10.5, or 16.11.2 or later.📡 Detection & Monitoring
Log Indicators:
- Unusually large markdown processing times
- Multiple markdown processing errors
- High CPU/memory usage from markdown parsing
Network Indicators:
- Increased traffic to markdown-related endpoints
- Timeouts on markdown processing requests
SIEM Query:
source="gitlab" AND ("markdown" OR "rendering") AND (error OR timeout OR "high latency")