CVE-2023-34091 Explained : Impact and Mitigation

A vulnerability has been identified in Kyverno, a policy engine for Kubernetes, which could allow policy circumvention. Below are the details of CVE-2023-34091 to help you understand the issue, its impact, technical details, and mitigation steps.

Understanding CVE-2023-34091

This section provides insight into the vulnerability present in Kyverno prior to version 1.10.0.

What is CVE-2023-34091?

Kyverno versions below 1.10.0 allow resources with a

deletionTimestamp

field to bypass certain policies, potentially enabling policy circumvention by malicious users.

The Impact of CVE-2023-34091

The vulnerability could be exploited by attackers to bypass policies on Kubernetes resources, such as Services, by leveraging the finalizers feature. This could lead to security breaches and unauthorized actions within Kubernetes environments.

Technical Details of CVE-2023-34091

This section outlines the specific aspects of the vulnerability in Kyverno.

Vulnerability Description

In Kyverno versions < 1.10.0, resources with a

deletionTimestamp

field defined can bypass certain policies, even with the

validationFailureAction

set to

Enforce

, allowing malicious actors to exploit the finalizers feature for policy circumvention.

Affected Systems and Versions

Kyverno versions earlier than 1.10.0 are impacted by this vulnerability, specifically resources with the

deletionTimestamp

field.

Exploitation Mechanism

Malicious users could leverage Kubernetes finalizers to set

deletionTimestamp

on resources, avoiding policy enforcement and executing unauthorized actions through policy bypass.

Mitigation and Prevention

To address CVE-2023-34091 and enhance security, follow the mitigation strategies outlined below.

Immediate Steps to Take

It is recommended to update Kyverno to version 1.10.0 or later to mitigate the vulnerability. Additionally, review and strengthen access controls and policies within Kubernetes environments.

Long-Term Security Practices

Implement regular security assessments, monitor for unauthorized actions, and educate users on secure Kubernetes practices to prevent future exploits.

Patching and Updates

Stay informed about security updates from Kyverno and promptly apply patches to ensure the latest security protocols are in place.