Horizon Alert
Summary of the vulnerability and why it matters
This advisory details a critical vulnerability in Gogs, an open-source self-hosted Git service, that allows authenticated users to execute arbitrary code on the server. The issue arises during a specific merge operation involving specially crafted branch names, potentially enabling unauthorized control over the affected systems. The main concern is confirming relevance and exposure.
- Crafted branch names allow code execution.
- Affects self-hosted Git services.
- Confirm if Gogs is in use.
Attack Path
How an attacker could exploit the issue
An attacker could leverage this vulnerability by first gaining authenticated access to the Gogs server. Once authenticated, they could craft a pull request with a malicious branch name. This crafted name would be processed during a "Rebase before merging" operation, causing the server to execute arbitrary commands and potentially leading to remote code execution.
- Authenticated access to the server is required.
- Specially named branch in pull request triggers vulnerability.
- Risk of full server compromise.
Live Threat
Current exploitation, exposure, and threat context
When supported by the advisory, authenticated users could achieve remote code execution on the server by creating a pull request with a specially crafted branch name that injects commands into the git rebase operation during a merge.
- Server code execution.
- Malicious branch name injection.
- Compromised server.
Operational Fix
Recommended remediation, mitigation, and detection steps
System owners and platform teams are likely responsible for addressing this vulnerability in Gogs, a self-hosted Git service. The first practical step is to identify all Gogs instances, assess their reachability and business criticality, and then assign ownership for remediation, planning updates during scheduled maintenance windows.
- Identify Gogs instances and owners.
- Verify reachability and business criticality.
- Plan remediation based on risk.
