CVE-2023-28768 : Security Advisory and Response

This CVE-2023-28768 advisory was published by Zyxel on August 14, 2023. It pertains to the improper frame handling in specific firmware versions of Zyxel switches, potentially leading to denial-of-service (DoS) attacks when exploited by an unauthenticated LAN-based attacker.

Understanding CVE-2023-28768

This section will delve into the details of CVE-2023-28768, including its impact, technical aspects, and mitigation strategies.

What is CVE-2023-28768?

CVE-2023-28768 involves improper frame handling in Zyxel XGS2220-30 firmware version V4.80(ABXN.1), XMG1930-30 firmware version V4.80(ACAR.1), and XS1930-10 firmware version V4.80(ABQE.1). This vulnerability could be exploited by an unauthenticated LAN-based attacker to trigger DoS conditions by sending crafted frames to the affected switch.

The Impact of CVE-2023-28768

The impact of CVE-2023-28768 is significant, as it could result in denial-of-service (DoS) conditions on the affected Zyxel switches. This vulnerability poses a threat to the availability of network services and operations, potentially disrupting normal network functionality.

Technical Details of CVE-2023-28768

In this section, we will explore the technical details of CVE-2023-28768, including vulnerability description, affected systems and versions, as well as the exploitation mechanism.

Vulnerability Description

The vulnerability in Zyxel switches due to improper frame handling in specific firmware versions could allow an unauthenticated LAN-based attacker to launch denial-of-service (DoS) attacks by sending crafted frames to the affected devices.

Affected Systems and Versions

The Zyxel switches affected by CVE-2023-28768 include XGS2220-30 firmware version V4.80(ABXN.1), XMG1930-30 firmware version V4.80(ACAR.1), and XS1930-10 firmware version V4.80(ABQE.1).

Exploitation Mechanism

The vulnerability in the specified Zyxel switch firmware versions can be exploited by an unauthenticated LAN-based attacker leveraging crafted frames to trigger denial-of-service (DoS) conditions on the targeted switches.

Mitigation and Prevention

Mitigating the risks associated with CVE-2023-28768 involves immediate steps to take, adopting long-term security practices, and ensuring timely application of patches and updates.

Immediate Steps to Take

Organizations should restrict network access to ensure only authorized users can interact with the vulnerable Zyxel switches.
Network administrators should monitor network traffic for any signs of abnormal activity that may indicate an ongoing exploitation attempt.

Long-Term Security Practices

Implementing network segmentation and access controls can help contain potential attacks and limit the impact of vulnerabilities like CVE-2023-28768.
Regular security assessments and audits of network devices can help identify and address vulnerabilities proactively.

Patching and Updates

Zyxel has likely released security updates or patches to address the vulnerability in the affected firmware versions. Organizations are advised to apply these patches promptly to secure their network infrastructure from potential exploitation.