CVE-2021-20198 : Security Advisory and Response

A flaw was discovered in the OpenShift Installer before version v0.9.0-master.0.20210125200451-95101da940b0. This vulnerability impacts the bootstrap nodes during the installation of OpenShift Container Platform 4 clusters, as they are provisioned with anonymous authentication enabled on kubelet port 10250. An unauthorized remote attacker can exploit this flaw by making unauthenticated

/exec

requests, allowing them to execute arbitrary commands within running containers, posing a significant risk to data confidentiality, integrity, and system availability.

Understanding CVE-2021-20198

This section delves deeper into the technical aspects and implications of CVE-2021-20198.

What is CVE-2021-20198?

The vulnerability in OpenShift Installer before version v0.9.0-master.0.20210125200451-95101da940b0 allows remote attackers to execute arbitrary commands in running containers by exploiting anonymous authentication on kubelet port 10250.

The Impact of CVE-2021-20198

The primary consequence of this vulnerability is the compromise of data confidentiality, integrity, and system availability when unauthorized attackers gain the ability to execute commands within containers.

Technical Details of CVE-2021-20198

This section provides more detailed technical insights into the CVE-2021-20198 vulnerability.

Vulnerability Description

The flaw in OpenShift Installer enables unauthenticated remote attackers to execute arbitrary commands in running containers, posing a severe security risk.

Affected Systems and Versions

OpenShift Installer versions before v0.9.0-master.0.20210125200451-95101da940b0 are vulnerable to this exploit.

Exploitation Mechanism

Attackers can leverage anonymous authentication on kubelet port 10250 to send unauthenticated

/exec

requests and execute arbitrary commands.

Mitigation and Prevention

To safeguard your systems and data, it is crucial to take immediate steps and implement long-term security measures.

Immediate Steps to Take

Disable anonymous authentication on kubelet port 10250 and monitor for any unauthorized access attempts.

Long-Term Security Practices

Implement network segmentation, access controls, and regular security audits to fortify system defenses.

Patching and Updates

Ensure you promptly update to OpenShift Installer version v0.9.0-master.0.20210125200451-95101da940b0 or newer to remediate this vulnerability.