A vulnerability (CVE-2024-9164) has been discovered in GitLab Enterprise Edition (EE) allowing malicious users to trigger pipelines on arbitrary branches. This vulnerability can lead to unauthorized code execution and compromising of sensitive information.

3. Impact

An attacker can exploit this vulnerability to run pipelines on arbitrary branches, potentially leading to unauthorized code execution on the target system. This can result in leakage or manipulation of sensitive data, and unauthorized system access.

4. Exploit Details

The vulnerability stems from an issue in the GitLab EE code where the branch validation was not properly implemented, allowing attackers to execute pipelines on any branches, instead of only the configured branches.

Here is a code snippet that demonstrates the vulnerability

# Vulnerable Python code example
def run_pipeline(branch_name):
    if validate_branch(branch_name): # This validation process is flawed
        pipeline = create_pipeline(branch_name)
        pipeline.execute()
    else:
        print('Invalid branch name')

def validate_branch(branch_name):
    # This function should properly validate the branch_name,
    # but the implementation is incorrect
    return True # Should be a real validation process and not a hardcoded True

if __name__ == "__main__":
    run_pipeline('arbitrary-branch')

Due to the incorrect branch validation process, an attacker can bypass the validation and trigger a pipeline on any given branch.

5. Mitigation

Users are strongly advised to update their GitLab EE installations to the latest secure version immediately, depending on the affected version range:

If using 17.4.x, update to version 17.4.2

Additionally, it is recommended to regularly check for GitLab EE updates and patches, and apply them promptly as they become available.

6. References

- CVE-2024-9164
- GitLab EE Security Release: 17.2.9, 17.3.5, 17.4.2
- GitLab EE Documentation - Branches

Timeline

Published on: 10/11/2024 13:15:17 UTC
Last modified on: 10/15/2024 12:58:51 UTC