CVE-2023-39347 : Vulnerability Insights and Analysis

This article provides detailed information about CVE-2023-39347, a vulnerability that allows Cilium NetworkPolicy bypass via pod labels.

Understanding CVE-2023-39347

This section explains the impact, technical details, and mitigation strategies related to CVE-2023-39347.

What is CVE-2023-39347?

CVE-2023-39347 involves a vulnerability in Cilium that allows an attacker with the ability to update pod labels to cause Cilium to apply incorrect network policies. This poses a risk to the security of affected systems.

The Impact of CVE-2023-39347

The vulnerability can be exploited by an attacker with Kubernetes API Server access to bypass network policies by providing non-existent construct names, leading to unauthorized access or unrestricted traffic within affected systems.

Technical Details of CVE-2023-39347

This section delves into the specifics of the vulnerability, affected systems, and how the exploitation can occur.

Vulnerability Description

Cilium incorrectly uses user-provided pod labels to select network policies, allowing an attacker to circumvent restrictions set by these policies and potentially compromise system security.

Affected Systems and Versions

Systems running Cilium versions >= 1.14.0 and < 1.14.2, >= 1.13.0 and < 1.13.7, and < 1.12.14 are susceptible to this vulnerability.

Exploitation Mechanism

Attackers leverage the incorrect usage of pod labels by Cilium to trick the system into applying unauthorized network policies, enabling them to bypass security measures.

Mitigation and Prevention

This section outlines steps to mitigate the risks posed by CVE-2023-39347 and prevent potential exploitation.

Immediate Steps to Take

Users are advised to upgrade to the patched versions of Cilium (1.14.2, 1.13.7, or 1.12.14) to address the vulnerability and enhance system security.

Long-Term Security Practices

Implementing admission webhooks to restrict pod label updates for specific keys can help prevent unauthorized changes and enhance security measures within the system.

Patching and Updates

Regularly updating Cilium to the latest secure versions is crucial in maintaining a secure network environment and safeguarding against potential vulnerabilities.