Git has been an invaluable tool for developers worldwide when it comes to managing and tracking changes in source code over time. However, a newly identified security risk, dubbed "GitBleed," has been discovered in Git versions through 2.35.1. This vulnerability could potentially lead to the exposure of deleted content that was earlier presumed to be inaccessible. In this article, we'll delve deep into the details of GitBleed, explain how it affects Git's --mirror documentation, and describe possible exploitation scenarios. Furthermore, we'll provide you with links to the original references and demonstrate essential code snippets related to the issue.

Issue Details

CVE-2022-24975, or "GitBleed," concerns the lack of proper documentation for Git's "--mirror" option. The vulnerability arises because the documentation does not explicitly mention the availability of deleted content when using a clone operation without the --mirror option. Consequently, if users or organizations rely on information-disclosure auditing processes based on clone operations without --mirror, they may unknowingly expose sensitive, deleted data.

In simple terms, when a Git repository is cloned without the --mirror option, previously deleted content from the repository may still be accessible. This accessibility raises potential security and privacy concerns that might not be apparent based on the current documentation.

A typical Git clone operation without the --mirror option looks like

$ git clone https://github.com/user/repo.git

To create a mirror copy of the repository, the --mirror option is used

$ git clone --mirror https://github.com/user/repo.git

Exploit Details

An attacker could exploit GitBleed by accessing a non-mirrored clone of a repository to retrieve sensitive information that was thought to be removed from the repository. Such data leaks may include passwords, confidential documents, or other valuable information.

The exposure results from the fact that when using the standard git clone command without the --mirror option, Git creates a new copy of the repository, along with its refs and objects. Objects are unique items in the Git database, including commits, trees, and blobs. When a file is deleted, and a commit is performed, the file's associated blob is no longer referenced. However, if an attacker knows the blob's hash or has a way to find it, they can still access the data from the cloned repository.

Mitigation

Users and organizations should consider enabling the --mirror option when cloning their Git repositories to prevent the possibility of exposing deleted content. Additionally, repository administrators should perform thorough audits and ensure that sensitive information removal is not solely dependent on the git clone command without the --mirror option. Moreover, staying up-to-date with Git's latest releases and security patches should always be a priority.

Original References

For a better understanding and more technical details, you may refer to the following original references:

1. Git's --mirror documentation
2. Common Vulnerabilities and Exposures (CVE)
3. National Vulnerability Database (NVD) on CVE-2022-24975

Conclusion

CVE-2022-24975, or "GitBleed," highlights the importance of thorough documentation and proper understanding of security implications when using widely adopted tools like Git. As developers and organizations, it is crucial to stay well-informed about potential vulnerabilities and adopt best practices to avoid unintended leaks of sensitive information. Ensuring that your development practices prioritize security and data privacy will ultimately contribute to a more robust software ecosystem.

Timeline

Published on: 02/11/2022 20:15:00 UTC
Last modified on: 02/22/2022 20:19:00 UTC