CVE-2021-35034 : Exploit Details and Defense Strategies

A vulnerability has been discovered in the Zyxel NBG6604 series firmware that could potentially allow a remote attacker to access the device by intercepting the correct token. This CVE has a CVSS base score of 7.4, indicating a high severity level.

Understanding CVE-2021-35034

This section will cover what CVE-2021-35034 entails, its impact, technical details, and mitigation steps.

What is CVE-2021-35034?

The CVE-2021-35034 vulnerability involves an insufficient session expiration flaw in the CGI program of Zyxel NBG6604 firmware, which could be exploited by attackers to gain unauthorized access.

The Impact of CVE-2021-35034

With a CVSS base score of 7.4 and high impacts on confidentiality, integrity, and no user interaction required, this vulnerability poses a significant risk to affected systems.

Technical Details of CVE-2021-35034

Below are specific technical details related to CVE-2021-35034:

Vulnerability Description

The vulnerability stems from inadequate session expiration in the firmware's CGI program, potentially granting unauthorized access to attackers.

Affected Systems and Versions

Zyxel NBG6604 firmware version 1.00(ABIR.8)C0 is known to be impacted by this vulnerability.

Exploitation Mechanism

Remote attackers can exploit this vulnerability by intercepting the correct token, allowing them to access the affected device remotely.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-35034, users and administrators should take the following immediate and long-term security measures:

Immediate Steps to Take

Monitor security advisories from Zyxel and apply patches promptly.
Implement network segmentation to limit the impact of potential attacks.

Long-Term Security Practices

Regularly update firmware and software to ensure systems are protected against known vulnerabilities.
Utilize strong authentication mechanisms and encryption protocols to secure device access.

Patching and Updates

Check Zyxel's official security advisory for CVE-2021-35034 to access and apply the necessary patches and updates to address this vulnerability.