CVE-2021-21666 Explained : Impact and Mitigation

Jenkins Kiuwan Plugin 1.6.0 and earlier versions are impacted by a reflected cross-site scripting (XSS) vulnerability due to the lack of escaping query parameters in an error message for a form validation endpoint.

Understanding CVE-2021-21666

This CVE record details the security issue within the Jenkins Kiuwan Plugin versions.

What is CVE-2021-21666?

CVE-2021-21666 is a cross-site scripting vulnerability in Jenkins Kiuwan Plugin versions, specifically affecting version 1.6.0 and earlier. The flaw allows for the injection of malicious scripts into web pages viewed by other users.

The Impact of CVE-2021-21666

Exploitation of this vulnerability could lead to unauthorized access, data theft, defacement, and other serious security breaches. Attackers can execute arbitrary code in the context of the user's browser, posing significant risks to affected systems.

Technical Details of CVE-2021-21666

This section provides a deeper look into the technical aspects of the CVE.

Vulnerability Description

The vulnerability arises from unescaped query parameters in error messages, enabling attackers to inject and execute malicious scripts in the context of a user's session.

Affected Systems and Versions

Jenkins Kiuwan Plugin versions up to and including 1.6.0 are susceptible to this XSS flaw, impacting systems with these plugin versions installed.

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting malicious URLs or forms that, when triggered, execute unauthorized scripts within the user's browser.

Mitigation and Prevention

Protecting systems from CVE-2021-21666 requires immediate actions and long-term security practices.

Immediate Steps to Take

Users should update the Jenkins Kiuwan Plugin to a secure version that includes a fix for the XSS vulnerability. Additionally, monitoring web requests and inputs for suspicious behavior can help detect possible exploitation.

Long-Term Security Practices

Implementing secure coding practices, such as input validation and output encoding, can prevent XSS vulnerabilities in plugins and applications. Regular security audits and updates are essential to maintaining a secure software environment.

Patching and Updates

Stay informed about security advisories and patches released by Jenkins project for the Jenkins Kiuwan Plugin. Promptly applying these updates can address known vulnerabilities and ensure the overall security of the system.