CVE-2021-21630 : What You Need to Know

Jenkins Extra Columns Plugin 1.22 and earlier versions are affected by a stored cross-site scripting (XSS) vulnerability due to the lack of escaping parameter values in the build parameters column. This vulnerability can be exploited by attackers with Job/Configure permission.

Understanding CVE-2021-21630

This section will cover the details of CVE-2021-21630, including the vulnerability description, impact, affected systems, and mitigation steps.

What is CVE-2021-21630?

CVE-2021-21630 is a stored cross-site scripting (XSS) vulnerability in Jenkins Extra Columns Plugin versions 1.22 and earlier. Attackers with Job/Configure permission can exploit this vulnerability.

The Impact of CVE-2021-21630

The impact of this vulnerability includes the potential for attackers to execute malicious scripts in the context of a victim's browser, leading to account takeover, data theft, and other forms of cyber attacks.

Technical Details of CVE-2021-21630

In this section, we will delve into the technical aspects of CVE-2021-21630, including the vulnerability description, affected systems, and exploitation mechanism.

Vulnerability Description

The vulnerability arises from the failure to properly escape parameter values in the build parameters column of Jenkins Extra Columns Plugin, allowing attackers to inject malicious scripts.

Affected Systems and Versions

Jenkins Extra Columns Plugin versions 1.22 and earlier are affected by this vulnerability. Users of these versions are at risk of exploitation by malicious actors.

Exploitation Mechanism

Attackers with Job/Configure permission can exploit this vulnerability by injecting malicious scripts into the build parameters column, which then get executed in the context of other users' browsers.

Mitigation and Prevention

This section provides guidance on mitigating the risks associated with CVE-2021-21630 and preventing potential exploitation.

Immediate Steps to Take

Users should update Jenkins Extra Columns Plugin to a fixed version that addresses the XSS vulnerability. Additionally, restricting Job/Configure permissions can help reduce the attack surface.

Long-Term Security Practices

Implementing secure coding practices, conducting regular security audits, and educating users about XSS attacks are essential for long-term security.

Patching and Updates

Stay informed about security advisories from Jenkins and apply patches promptly to secure the Jenkins environment against known vulnerabilities.