CVE-2021-21689 : Exploit Details and Defense Strategies
Learn about CVE-2021-21689, a security flaw in Jenkins <= 2.318 and LTS 2.303.2 allowing unauthorized agent-to-controller access during file operations. Find out how to mitigate this vulnerability.
A security vulnerability with the ID CVE-2021-21689 has been identified in Jenkins, affecting versions <= 2.318 and LTS 2.303.2. The vulnerability allowed unauthorized access to FilePath#unzip and FilePath#untar without proper access control.
Understanding CVE-2021-21689
This section explains the details of the CVE-2021-21689 vulnerability in Jenkins.
What is CVE-2021-21689?
The vulnerability in Jenkins, tracked as CVE-2021-21689, allowed unauthorized agent-to-controller access in versions <= 2.318 and LTS 2.303.2 during file operations.
The Impact of CVE-2021-21689
The security flaw could be exploited by malicious actors to perform unauthorized file extraction operations within Jenkins instances, potentially leading to unauthorized access or data manipulation.
Technical Details of CVE-2021-21689
This section provides technical insights into the CVE-2021-21689 vulnerability.
Vulnerability Description
FilePath#unzip and FilePath#untar functions in Jenkins versions <= 2.318 and LTS 2.303.2 lacked necessary access control measures, allowing unauthorized file extraction.
Affected Systems and Versions
Jenkins versions affected by CVE-2021-21689 include <= 2.318 and LTS 2.303.2.
Exploitation Mechanism
Malicious actors could exploit this vulnerability to gain unauthorized access to perform file extraction operations within Jenkins environments.
Mitigation and Prevention
In this section, we discuss how to mitigate and prevent the CVE-2021-21689 vulnerability in Jenkins.
Immediate Steps to Take
Ensure Jenkins instances are updated to versions that include fixes for the vulnerability. Implement access controls to restrict unauthorized file operations.
Long-Term Security Practices
Regularly monitor Jenkins security advisories and apply updates promptly to prevent potential security risks. Follow best practices for access control and privilege management.
Patching and Updates
Stay informed about security updates released by Jenkins and promptly apply patches to eliminate known vulnerabilities.