CVE-2021-4029 : Exploit Details and Defense Strategies
Learn about CVE-2021-4029 affecting Zyxel ARMOR Z1/Z2 firmware, allowing attackers to execute malicious OS commands. Discover the impact, affected systems, and mitigation steps.
A command injection vulnerability in the CGI program of the Zyxel ARMOR Z1/Z2 firmware could allow an attacker to execute arbitrary OS commands via a LAN interface.
Understanding CVE-2021-4029
This CVE identifies a severe vulnerability in the Zyxel ARMOR Z1 and Z2 firmware that could lead to the execution of unauthorized OS commands.
What is CVE-2021-4029?
The CVE-2021-4029 vulnerability is a command injection flaw in the CGI program of the Zyxel ARMOR Z1/Z2 firmware, which enables attackers to run arbitrary OS commands through a LAN interface.
The Impact of CVE-2021-4029
The impact of CVE-2021-4029 is significant, with a base score of 8.8 and high severity, affecting both confidentiality and integrity. If exploited, it could result in complete compromise and unauthorized access to affected systems.
Technical Details of CVE-2021-4029
This section covers specific technical details of the CVE.
Vulnerability Description
The vulnerability arises from improper neutralization of special elements used in an OS command, allowing threat actors to inject and execute malicious commands.
Affected Systems and Versions
The affected products include Zyxel ARMOR Z1 (NBG6816) with firmware version 1.00(AAWB.10)C0 and Zyxel ARMOR Z2 (NBG6817) with firmware version 1.00(ABCS.10)C0.
Exploitation Mechanism
Attackers can exploit this vulnerability through the LAN interface, executing unauthorized OS commands via the CGI program.
Mitigation and Prevention
To address CVE-2021-4029, immediate action and long-term security measures are necessary.
Immediate Steps to Take
Update the firmware to the latest version provided by Zyxel to patch the vulnerability. Ensure strict access controls and monitor network traffic for any suspicious activities.
Long-Term Security Practices
Regularly update and patch all network devices, conduct security assessments, and implement network segmentation to minimize the attack surface.
Patching and Updates
Stay informed about security advisories from Zyxel and promptly apply patches to protect against known vulnerabilities.