CVE-2025-0811
📋 TL;DR
This cross-site scripting vulnerability in GitLab allows attackers to inject malicious scripts through improperly rendered file types. When exploited, it can lead to session hijacking, data theft, or unauthorized actions in the context of the victim's GitLab session. All GitLab CE/EE instances running affected versions are vulnerable.
💻 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 steal administrator credentials, compromise the entire GitLab instance, access sensitive source code, and pivot to internal systems.
Likely Case
Attackers steal user session cookies, perform unauthorized actions on behalf of victims, or exfiltrate sensitive repository data.
If Mitigated
With proper CSP headers and input validation, impact is limited to the specific vulnerable file rendering component.
🎯 Exploit Status
Exploitation requires user interaction with malicious content and knowledge of specific file types that trigger the improper rendering.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 17.8.6, 17.9.3, or 17.10.1
Vendor Advisory: https://gitlab.com/gitlab-org/gitlab/-/issues/515566
Restart Required: No
Instructions:
1. Backup your GitLab instance. 2. Update to GitLab 17.8.6, 17.9.3, or 17.10.1 using your preferred method (Omnibus package, Docker, source). 3. Verify the update completed successfully.
🔧 Temporary Workarounds
Disable file preview for untrusted sources
allConfigure GitLab to disable automatic rendering of file types that could trigger the vulnerability
🧯 If You Can't Patch
- Implement strict Content Security Policy headers to mitigate XSS impact
- Restrict user uploads and file sharing capabilities to trusted users only
🔍 How to Verify
Check if Vulnerable:
Check GitLab version via Admin Area or run: sudo gitlab-rake gitlab:env:info | grep 'GitLab version'Check Version:
sudo gitlab-rake gitlab:env:info | grep 'GitLab version'Verify Fix Applied:
Confirm version is 17.8.6, 17.9.3, or 17.10.1 after update📡 Detection & Monitoring
Log Indicators:
- Unusual file upload patterns
- Multiple failed file rendering attempts
- Suspicious user agent strings in file access logs
Network Indicators:
- Unexpected outbound connections after file uploads
- Patterns of malicious script delivery in HTTP requests
SIEM Query:
source="gitlab" AND ("file upload" OR "render" OR "preview") AND status=200 AND user_agent CONTAINS suspicious_pattern