CVE-2020-2161 Explained : Impact and Mitigation

Jenkins 2.227 and earlier, LTS 2.204.5 and earlier versions are affected by a stored XSS vulnerability due to improper escaping of node labels in job configuration pages.

Understanding CVE-2020-2161

This CVE involves a security issue in Jenkins versions that could be exploited by users defining node labels.

What is CVE-2020-2161?

CVE-2020-2161 is a Cross-Site Scripting (XSS) vulnerability in Jenkins versions 2.227 and earlier, LTS 2.204.5 and earlier, allowing users to execute malicious scripts.

The Impact of CVE-2020-2161

The vulnerability enables attackers to inject and execute arbitrary scripts within the context of the user's session, potentially leading to unauthorized actions or data theft.

Technical Details of CVE-2020-2161

Jenkins 2.227 and earlier, LTS 2.204.5 and earlier are susceptible to this XSS vulnerability.

Vulnerability Description

The flaw arises from the inadequate handling of node labels in job configuration pages, permitting stored XSS attacks by users with label definition privileges.

Affected Systems and Versions

Jenkins versions <= 2.227
LTS versions <= 2.204.5

Exploitation Mechanism

Attackers with the ability to define node labels can exploit this vulnerability by injecting malicious scripts into the label expressions on job configuration pages.

Mitigation and Prevention

Taking immediate action and implementing long-term security practices are crucial to mitigate the risks associated with CVE-2020-2161.

Immediate Steps to Take

Upgrade Jenkins to a patched version that addresses the XSS vulnerability.
Restrict user privileges to minimize the impact of potential attacks.

Long-Term Security Practices

Regularly monitor and audit configurations and user permissions within Jenkins.
Educate users on secure coding practices to prevent XSS vulnerabilities.

Patching and Updates

Apply security patches provided by Jenkins to fix the XSS vulnerability and enhance overall system security.