CVE-2020-2096 Explained : Impact and Mitigation

Jenkins Gitlab Hook Plugin 1.4.2 and earlier versions are vulnerable to reflected XSS due to unescaped project names in the build_now endpoint.

Understanding CVE-2020-2096

This CVE involves a security vulnerability in the Jenkins Gitlab Hook Plugin that allows for reflected XSS attacks.

What is CVE-2020-2096?

CVE-2020-2096 is a vulnerability in Jenkins Gitlab Hook Plugin versions 1.4.2 and earlier, where unescaped project names in the build_now endpoint can lead to a reflected XSS risk.

The Impact of CVE-2020-2096

The vulnerability could allow an attacker to execute malicious scripts in the context of a user's browser, potentially leading to unauthorized actions or data theft.

Technical Details of CVE-2020-2096

This section provides more in-depth technical information about the CVE.

Vulnerability Description

The issue arises from the lack of proper escaping of project names in the build_now endpoint, enabling attackers to inject and execute malicious scripts.

Affected Systems and Versions

Product: Jenkins Gitlab Hook Plugin
Vendor: Jenkins project
Vulnerable Versions: <= 1.4.2

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting a malicious link containing a specially crafted project name that, when clicked by a user with the affected plugin, executes the injected script.

Mitigation and Prevention

Protecting systems from CVE-2020-2096 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update the Jenkins Gitlab Hook Plugin to a non-vulnerable version.
Implement input validation to prevent script injection.

Long-Term Security Practices

Regularly monitor and update plugins and dependencies.
Educate users on safe browsing practices to avoid clicking on suspicious links.

Patching and Updates

Ensure timely installation of security patches and updates provided by Jenkins to address the vulnerability.