CVE-2022-0871
📋 TL;DR
CVE-2022-0871 is a missing authorization vulnerability in Gogs (a self-hosted Git service) that allows attackers to bypass authentication and access unauthorized repositories. This affects all Gogs instances running versions prior to 0.12.5. Attackers can exploit this to view private repositories they shouldn't have access to.
💻 Affected Systems
- Gogs (Go Git Service)
📦 What is this software?
Gogs by Gogs
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of all private repositories, including sensitive source code, credentials, and intellectual property exposure.
Likely Case
Unauthorized access to private repositories leading to source code theft, credential harvesting, and potential supply chain attacks.
If Mitigated
Limited impact with proper network segmentation and access controls, but still exposes repository contents to unauthorized users.
🎯 Exploit Status
The vulnerability is straightforward to exploit - attackers can access unauthorized repositories via crafted HTTP requests. Public proof-of-concept code exists.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.12.5 and later
Vendor Advisory: https://github.com/gogs/gogs/security/advisories/GHSA-4h98-2769-gh6h
Restart Required: Yes
Instructions:
1. Backup your Gogs data and configuration. 2. Stop the Gogs service. 3. Update to version 0.12.5 or later using your package manager or by downloading from GitHub. 4. Restart the Gogs service. 5. Verify the update was successful.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict network access to Gogs instance to trusted IPs only
# Using iptables (Linux): iptables -A INPUT -p tcp --dport 3000 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 3000 -j DROP
Reverse Proxy Authentication
allPlace Gogs behind a reverse proxy with additional authentication layer
# Example nginx config with basic auth
location / {
auth_basic "Restricted";
auth_basic_user_file /etc/nginx/.htpasswd;
proxy_pass http://localhost:3000;
}
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to limit access to Gogs instance
- Enable audit logging and monitor for unauthorized repository access attempts
🔍 How to Verify
Check if Vulnerable:
Check Gogs version via web interface (Admin Panel → Configuration) or command line: ./gogs --versionCheck Version:
./gogs --versionVerify Fix Applied:
Verify version is 0.12.5 or later and test that unauthorized users cannot access private repositories📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to private repositories
- HTTP 200 responses for repository access from unauthenticated users
- Access patterns showing users viewing repositories they don't have permissions for
Network Indicators:
- Unusual HTTP GET requests to repository endpoints from unauthorized IPs
- Increased traffic to /:username/:reponame.git endpoints
SIEM Query:
source="gogs.log" AND (http_status=200) AND (user="anonymous" OR auth_method="none") AND uri="/.*/.*.git"