CVE-2025-1250
📋 TL;DR
This vulnerability allows authenticated GitLab users to disrupt background job processing by submitting malicious content in commit messages, merge request descriptions, or notes. It affects all GitLab CE/EE instances running vulnerable versions, potentially causing service degradation. The attack requires valid user credentials but can impact system 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 denial of service where background job processing is permanently stalled, preventing code deployments, CI/CD pipelines, and other automated workflows from functioning.
Likely Case
Temporary service degradation where background jobs are delayed or fail, impacting development workflows and automated processes until manual intervention.
If Mitigated
Minimal impact with proper monitoring and alerting that detects stalled jobs quickly, allowing administrators to restart affected services before significant disruption.
🎯 Exploit Status
Exploitation requires authenticated access and knowledge of specific payloads that trigger the processing stall. The vulnerability was responsibly disclosed through HackerOne.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 18.1.6, 18.2.6, or 18.3.2
Vendor Advisory: https://about.gitlab.com/releases/2025/09/10/patch-release-gitlab-18-3-2-released/
Restart Required: No
Instructions:
1. Backup your GitLab instance. 2. Update to GitLab 18.1.6, 18.2.6, or 18.3.2 depending on your current version. 3. Verify the update completed successfully. 4. Monitor background job processing.
🔧 Temporary Workarounds
Restrict user permissions
allLimit authenticated users' ability to create commit messages, merge requests, or notes to trusted personnel only.
Monitor background jobs
allImplement monitoring for stalled background jobs with automated alerts to administrators.
🧯 If You Can't Patch
- Implement strict access controls to limit which users can create content that triggers background jobs.
- Deploy network segmentation to isolate GitLab instances from critical production systems.
🔍 How to Verify
Check if Vulnerable:
Check your GitLab version against the affected ranges: 15.0-18.1.5, 18.2-18.2.5, or 18.3-18.3.1.Check Version:
sudo gitlab-rake gitlab:env:info | grep 'Version:'Verify Fix Applied:
Confirm your GitLab version is 18.1.6, 18.2.6, or 18.3.2 or higher, and monitor background job processing for normal operation.📡 Detection & Monitoring
Log Indicators:
- Unusually long background job processing times
- Failed or stalled Sidekiq jobs in logs
- Multiple jobs stuck in 'running' state
Network Indicators:
- Increased HTTP 500 errors from GitLab API endpoints
- Timeouts on job-related endpoints
SIEM Query:
source="gitlab.log" AND ("background job stalled" OR "Sidekiq timeout" OR "job processing delay")