CVE-2023-43498 : Security Advisory and Response

Jenkins 2.423 and earlier, LTS 2.414.1 and earlier, are affected by a vulnerability where processing file uploads using MultipartFormDataParser can create temporary files with default permissions, potentially allowing unauthorized access to read and write files on the Jenkins controller.

Understanding CVE-2023-43498

This section covers the details and impact of CVE-2023-43498.

What is CVE-2023-43498?

CVE-2023-43498 is a vulnerability in Jenkins versions 2.423 and earlier, LTS 2.414.1 and earlier, that allows attackers with access to the Jenkins controller file system to read and write temporary files created during file uploads.

The Impact of CVE-2023-43498

The vulnerability could be exploited by unauthorized parties to access sensitive information or inject malicious files into the Jenkins controller system, potentially leading to further compromise of the Jenkins environment.

Technical Details of CVE-2023-43498

This section dives into the specifics of the vulnerability.

Vulnerability Description

In Jenkins 2.423 and earlier, LTS 2.414.1 and earlier, processing file uploads using MultipartFormDataParser creates temporary files in the default system temporary directory with default permissions for newly created files, allowing unauthorized access.

Affected Systems and Versions

Product: Jenkins
Vendor: Jenkins Project
Versions:
Jenkins 2.423 and earlier
LTS 2.414.1 and earlier

Exploitation Mechanism

Attackers with access to the Jenkins controller file system could exploit this vulnerability by manipulating the temporary files created during file upload processes.

Mitigation and Prevention

This section outlines steps to mitigate and prevent exploitation of CVE-2023-43498.

Immediate Steps to Take

Update Jenkins to the latest version to patch the vulnerability.
Restrict access to the Jenkins controller system to authorized personnel only.

Long-Term Security Practices

Implement strict file permission settings on the Jenkins controller to limit unauthorized access to sensitive files.

Patching and Updates

Regularly update Jenkins to the latest versions to ensure known vulnerabilities are addressed and security features are up-to-date.