CVE-2021-21687 : Vulnerability Insights and Analysis

Jenkins 2.318 and LTS 2.303.2 and earlier versions are affected by a vulnerability that allows unarchiving symbolic links without checking agent-to-controller access, potentially leading to a security breach.

Understanding CVE-2021-21687

This CVE identifies a security issue in Jenkins versions 2.318 and LTS 2.303.2 and earlier, exposing them to a specific type of attack.

What is CVE-2021-21687?

CVE-2021-21687 relates to a flaw in Jenkins that allows unauthorized symbolic links to be created during unarchiving without proper access verification.

The Impact of CVE-2021-21687

The vulnerability could be exploited by attackers to manipulate symbolic links and potentially gain unauthorized access, compromising the security of Jenkins instances.

Technical Details of CVE-2021-21687

The following details outline the technical aspects of CVE-2021-21687.

Vulnerability Description

The vulnerability in Jenkins versions 2.318 and LTS 2.303.2 and earlier allows the creation of symbolic links without adequate access validation during unarchiving, posing a security risk.

Affected Systems and Versions

Jenkins versions 2.318 and LTS 2.303.2 and earlier are impacted by this vulnerability, exposing instances running these versions to potential exploitation.

Exploitation Mechanism

Exploiting CVE-2021-21687 involves manipulating symbolic links during the unarchiving process to bypass access controls and potentially compromise Jenkins environments.

Mitigation and Prevention

Protecting your system against CVE-2021-21687 requires immediate action and ongoing security measures.

Immediate Steps to Take

Users of affected Jenkins versions should apply relevant patches and updates as soon as possible to prevent exploitation of the vulnerability.

Long-Term Security Practices

Implementing robust access controls, regular security audits, and monitoring symbolic link creation can enhance the overall security posture of Jenkins instances.

Patching and Updates

Stay informed about security advisories from Jenkins and promptly apply patches and updates to address known vulnerabilities and maintain a secure Jenkins environment.