CVE-2020-2231 Explained : Impact and Mitigation
Learn about CVE-2020-2231 affecting Jenkins versions 2.251 and earlier, LTS 2.235.3 and earlier. Find mitigation steps and best practices for preventing stored cross-site scripting attacks.
Jenkins 2.251 and earlier, LTS 2.235.3 and earlier have a stored cross-site scripting (XSS) vulnerability that can be exploited by users with specific permissions or knowledge of the Authentication Token.
Understanding CVE-2020-2231
This CVE affects Jenkins versions 2.251 and earlier, LTS 2.235.3 and earlier, allowing for stored XSS attacks.
What is CVE-2020-2231?
- Jenkins versions prior to 2.251 and LTS versions before 2.235.3 do not properly escape the remote host's address when initiating a build via 'Trigger builds remotely', leading to a stored cross-site scripting vulnerability.
The Impact of CVE-2020-2231
- Users with Job/Configure permission or familiarity with the Authentication Token can exploit this vulnerability to execute malicious scripts within the context of the Jenkins application.
Technical Details of CVE-2020-2231
This section provides more technical insights into the vulnerability.
Vulnerability Description
- CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Systems and Versions
- Jenkins versions <= 2.251
- LTS versions <= 2.235.3
Exploitation Mechanism
- Attackers with Job/Configure permission or knowledge of the Authentication Token can inject and execute malicious scripts through the 'Trigger builds remotely' feature.
Mitigation and Prevention
Protect your systems from CVE-2020-2231 with these mitigation strategies.
Immediate Steps to Take
- Upgrade Jenkins to a version that includes a patch for this vulnerability.
- Restrict Job/Configure permissions to trusted users only.
- Regularly monitor and audit Jenkins configurations for unauthorized changes.
Long-Term Security Practices
- Implement secure coding practices to prevent XSS vulnerabilities in custom scripts.
- Educate users on the risks of sharing Authentication Tokens and best practices for securing them.
Patching and Updates
- Stay informed about security advisories from Jenkins and promptly apply patches to address known vulnerabilities.