CVE-2021-23021 Explained : Impact and Mitigation

Nginx Controller 3.x before version 3.7.0 has a vulnerability where the agent configuration file is world-readable with incorrect permission settings.

Understanding CVE-2021-23021

This CVE highlights a security issue in Nginx Controller versions prior to 3.7.0, making sensitive files accessible due to incorrect permission configuration.

What is CVE-2021-23021?

The agent configuration file '/etc/controller-agent/agent.conf' in Nginx Controller 3.x before 3.7.0 is world-readable with incorrect permission settings (644), potentially exposing sensitive information.

The Impact of CVE-2021-23021

This vulnerability could allow unauthorized users to read potentially sensitive data from the agent configuration file, leading to a compromise of confidentiality.

Technical Details of CVE-2021-23021

This section delves into the specific technical details of the CVE.

Vulnerability Description

The issue lies in the incorrect permission settings of the agent configuration file, making it world-readable instead of restricted access.

Affected Systems and Versions

Nginx Controller versions 3.x before 3.7.0 are affected by this vulnerability due to the world-readable agent configuration file.

Exploitation Mechanism

Attackers with access to the system can exploit this misconfiguration to read sensitive information from the exposed file.

Mitigation and Prevention

Discover how to address and prevent the CVE from affecting your systems.

Immediate Steps to Take

Ensure proper permissions are set for the agent configuration file to restrict access and prevent unauthorized reading.

Long-Term Security Practices

Implement a security review process to regularly check and adjust file permissions to avoid similar vulnerabilities in the future.

Patching and Updates

Upgrade Nginx Controller to version 3.7.0 or later, where the incorrect permission setting in the agent configuration file has been corrected.