CVE-2023-37926 Explained : Impact and Mitigation

A buffer overflow vulnerability in Zyxel products could potentially lead to denial-of-service (DoS) attacks. Here is an in-depth analysis of CVE-2023-37926:

Understanding CVE-2023-37926

This section delves into the specifics of the CVE-2023-37926 vulnerability.

What is CVE-2023-37926?

The vulnerability involves a buffer overflow issue in Zyxel ATP series firmware versions 4.32 through 5.37, USG FLEX series firmware versions 4.50 through 5.37, USG FLEX 50(W) series firmware versions 4.16 through 5.37, USG20(W)-VPN series firmware versions 4.16 through 5.37, and VPN series firmware versions 4.30 through 5.37. An authenticated local attacker could exploit this flaw to trigger DoS conditions by executing a CLI command to dump system logs on the affected device.

The Impact of CVE-2023-37926

The impact of this vulnerability is classified as MEDIUM with a base score of 5.5. The attack complexity is low, and the availability impact is high. No confidentiality or integrity impact is reported, and low privileges are required for exploitation. The attack vector is local, and user interaction is not necessary.

Technical Details of CVE-2023-37926

Delving into the technical aspects of this vulnerability.

Vulnerability Description

The vulnerability arises from a buffer overflow in multiple Zyxel firmware versions, potentially leading to DoS attacks.

Affected Systems and Versions

Zyxel products impacted by this vulnerability include ATP series firmware versions 4.32 through 5.37, USG FLEX series firmware versions 4.50 through 5.37, USG FLEX 50(W) series firmware versions 4.16 through 5.37, USG20(W)-VPN series firmware versions 4.16 through 5.37, and VPN series firmware versions 4.30 through 5.37.

Exploitation Mechanism

The vulnerability can be exploited by an authenticated local attacker executing CLI commands to dump system logs, causing DoS conditions.

Mitigation and Prevention

Understanding how to mitigate and prevent the CVE-2023-37926 vulnerability.

Immediate Steps to Take

Users are advised to apply security patches provided by Zyxel to address the buffer overflow vulnerability. Implementing proper access controls and monitoring CLI commands can also help mitigate risks.

Long-Term Security Practices

Regularly updating firmware, conducting security assessments, and ensuring appropriate user permissions are essential for long-term security.

Patching and Updates

Stay informed about security advisories from Zyxel and promptly apply recommended patches to protect against potential exploits.