CVE-2021-37915 : What You Need to Know

This CVE record pertains to a security issue identified in the Grandstream HT801 Analog Telephone Adaptor before version 1.0.29.8. The vulnerability allows an attacker to manipulate a specific variable through the device's configuration shell, leading to the execution of malicious scripts upon reboot.

Understanding CVE-2021-37915

This section provides insights into the nature of the CVE-2021-37915 vulnerability.

What is CVE-2021-37915?

The Grandstream HT801 Analog Telephone Adaptor, when running a version prior to 1.0.29.8, is susceptible to an exploit that enables threat actors to alter critical configurations and execute harmful scripts from a predefined source after restarting the device.

The Impact of CVE-2021-37915

The exploitation of this vulnerability can result in unauthorized remote code execution, potentially granting attackers control over the affected Grandstream HT801 device and compromising the integrity of the network it's connected to.

Technical Details of CVE-2021-37915

In this section, we delve into the technical aspects of CVE-2021-37915 to gain a comprehensive understanding of the security issue.

Vulnerability Description

The flaw in the Grandstream HT801 Analog Telephone Adaptor allows the setting of a dangerous gdb_debug_server variable via the limited configuration shell. As a consequence, the device fetches and executes malevolent scripts hosted by an adversary post-reboot.

Affected Systems and Versions

The vulnerability impacts Grandstream HT801 Analog Telephone Adaptors running firmware versions earlier than 1.0.29.8, exposing them to exploitation by malicious actors.

Exploitation Mechanism

By manipulating the gdb_debug_server configuration parameter, threat actors can implant and trigger malicious scripts on the HT801 device, leading to unauthorized code execution.

Mitigation and Prevention

This section outlines crucial steps to mitigate the risks associated with CVE-2021-37915 and prevent potential security breaches.

Immediate Steps to Take

It is advisable to update the Grandstream HT801 Analog Telephone Adaptor to the latest firmware version 1.0.29.8 or above, which patches the identified vulnerability and enhances the device's security posture.

Long-Term Security Practices

Implementing network segmentation, enforcing least privilege access controls, and conducting regular security audits are essential practices to fortify the security of connected devices and networks.

Patching and Updates

Regularly monitoring for firmware updates released by Grandstream and promptly applying patches to address known vulnerabilities is paramount in maintaining the security and integrity of the HT801 Analog Telephone Adaptor.