CVE-2023-2728 : Security Advisory and Response

This CVE-2023-2728 article provides detailed information about a security vulnerability in Kubernetes and its impact.

Understanding CVE-2023-2728

CVE-2023-2728 involves bypassing the enforce mountable secrets policy enforced by the ServiceAccount admission plugin in Kubernetes clusters. It allows users to launch containers that bypass the policy when using ephemeral containers.

What is CVE-2023-2728?

The vulnerability enables users to bypass the mountable secrets policy, which typically restricts pods running with a service account to reference only the specified secrets in the service account's secrets field. This issue affects Kubernetes clusters that utilize the ServiceAccount admission plugin and the

kubernetes.io/enforce-mountable-secrets

annotation with ephemeral containers.

The Impact of CVE-2023-2728

With a CVSS v3.1 base score of 6.5 (Medium severity), CVE-2023-2728 poses a risk to the confidentiality and integrity of affected systems. The attack complexity is low, and the privileges required are high, making it a notable vulnerability for Kubernetes environments.

Technical Details of CVE-2023-2728

This section outlines specific technical details of the CVE-2023-2728 vulnerability.

Vulnerability Description

Users can exploit the vulnerability to bypass the mountable secrets policy imposed by the ServiceAccount admission plugin, potentially compromising confidentiality and integrity within Kubernetes clusters.

Affected Systems and Versions

Versions affected by CVE-2023-2728 include Kubernetes v1.24.14, v1.25.0 - v1.25.10, v1.26.0 - v1.26.5, and v1.27.0 - v1.27.2.

Exploitation Mechanism

The vulnerability can be exploited by launching containers that circumvent the mountable secrets policy when ephemeral containers are used in conjunction with the ServiceAccount admission plugin.

Mitigation and Prevention

To address CVE-2023-2728 and enhance the security of Kubernetes clusters, proactive measures should be taken.

Immediate Steps to Take

Users are advised to upgrade Kubernetes to mitigate the vulnerability. Detailed instructions on upgrading Kubernetes can be found on the official Kubernetes documentation.

Long-Term Security Practices

Implementing proper access controls, regularly updating Kubernetes versions, and monitoring for unusual container behavior can enhance long-term security within Kubernetes environments.

Patching and Updates

Regularly applying security patches and staying informed about Kubernetes security advisories can help prevent potential exploits related to CVE-2023-2728.