Overview
In the realm of cybersecurity, the discovery of new vulnerabilities and their subsequent mitigation is a constant cycle. One such recently identified vulnerability is CVE-2024-56731, a serious security flaw that affects Gogs, an open-source, self-hosted Git service. This vulnerability allows unprivileged users to execute arbitrary commands on the Gogs instance, potentially leading to system compromise or data leakage. This issue is of high importance due to the widespread use of Gogs and the severity of the potential impact.
Vulnerability Summary
CVE ID: CVE-2024-56731
Severity: Critical (CVSS: 10.0)
Attack Vector: Network
Privileges Required: Low
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
Escape the Surveillance Era
Most apps won’t tell you the truth.
They’re part of the problem.
Phone numbers. Emails. Profiles. Logs.
It’s all fuel for surveillance.
Ameeba Chat gives you a way out.
- • No phone number
- • No email
- • No personal info
- • Anonymous aliases
- • End-to-end encrypted
Chat without a trace.
Product | Affected Versions
Gogs | Prior to 0.13.3
How the Exploit Works
The vulnerability lies in the insufficient patch for CVE-2024-39931. This flaw makes it possible to delete files under the .git directory and achieve remote command execution. Unprivileged users can exploit this loophole to run arbitrary commands on the Gogs instance with the privileges of the account specified by RUN_USER in the configuration. This can potentially allow attackers to access and modify any user’s code hosted on the same instance.
Conceptual Example Code
The following is a conceptual example of a shell command that an attacker might use to exploit this vulnerability:
$ curl -X DELETE http://target.example.com/.git/config
$ echo "command to execute" > exploit
$ curl -X PUT --upload-file exploit http://target.example.com/.git/hooks/post-updateIn this example, the attacker is first deleting the `.git` config file. They then create a new file `exploit` containing the command they wish to execute. Finally, they upload this file to the `post-update` hook, which will be triggered to run their command the next time the repository is updated.
Mitigation
The vulnerability has been patched in Gogs version 0.13.3, and updating to this version or later is recommended. If updating is not an immediate option, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as temporary mitigation. However, these options should be considered as temporary measures, and updating to a patched version should be done as soon as possible to prevent potential exploits.