CVE-2020-2221 Explained : Impact and Mitigation
Learn about CVE-2020-2221 affecting Jenkins versions 2.244 and earlier, LTS 2.235.1 and earlier. Find out the impact, technical details, and mitigation steps for this cross-site scripting vulnerability.
Jenkins 2.244 and earlier, LTS 2.235.1 and earlier versions are affected by a stored cross-site scripting vulnerability due to improper escaping of the upstream job's display name.
Understanding CVE-2020-2221
This CVE affects Jenkins versions 2.244 and earlier, LTS 2.235.1 and earlier.
What is CVE-2020-2221?
CVE-2020-2221 is a vulnerability in Jenkins that allows for stored cross-site scripting due to a lack of proper escaping of the upstream job's display name.
The Impact of CVE-2020-2221
The vulnerability can be exploited by 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-2020-2221
Jenkins versions 2.244 and earlier, LTS 2.235.1 and earlier are susceptible to this vulnerability.
Vulnerability Description
The issue arises from the failure to escape the upstream job's display name, allowing for the injection of malicious scripts.
Affected Systems and Versions
- Jenkins versions <= 2.244
- LTS versions <= 2.235.1
Exploitation Mechanism
Attackers can exploit this vulnerability by injecting malicious scripts into the display name of an upstream job, which are then executed in the context of a user's browser.
Mitigation and Prevention
It is crucial to take immediate steps to address and prevent the exploitation of CVE-2020-2221.
Immediate Steps to Take
- Upgrade Jenkins to a non-vulnerable version immediately.
- Implement input validation and output encoding to prevent XSS attacks.
- Monitor and restrict user inputs to prevent script injection.
Long-Term Security Practices
- Regularly update Jenkins and its plugins to the latest versions.
- Conduct security audits and code reviews to identify and mitigate vulnerabilities.
- Educate users on safe coding practices and the risks of XSS attacks.
Patching and Updates
- Apply patches provided by Jenkins to fix the vulnerability.
- Stay informed about security advisories and updates from Jenkins to address potential security issues.