CVE-2021-27254 : Exploit Details and Defense Strategies

A detailed overview of CVE-2021-27254 affecting NETGEAR R7800 routers.

Understanding CVE-2021-27254

This CVE involves a vulnerability that allows network-adjacent attackers to bypass authentication on affected NETGEAR R7800 installations without the need for authentication.

What is CVE-2021-27254?

This vulnerability in NETGEAR R7800 routers resides in the apply_save.cgi endpoint, resulting from the use of a hard-coded encryption key. Exploiting this flaw enables attackers to execute arbitrary code with root privileges.

The Impact of CVE-2021-27254

The CVSS V3.0 base score for this CVE is 6.3, categorizing it as of medium severity. Attack complexity is low, and no user interaction or privileges are required. The confidentiality, integrity, and availability impacts are all low.

Technical Details of CVE-2021-27254

This section covers specific technical aspects of the CVE.

Vulnerability Description

The vulnerability allows attackers to execute arbitrary code on affected NETGEAR R7800 devices due to a hard-coded encryption key in the apply_save.cgi endpoint.

Affected Systems and Versions

NETGEAR R7800 devices with firmware version 1.0.2.76 are impacted by this vulnerability.

Exploitation Mechanism

Attackers can exploit this vulnerability by leveraging the hard-coded encryption key to bypass authentication and execute code as root.

Mitigation and Prevention

Discover the necessary steps to safeguard against CVE-2021-27254.

Immediate Steps to Take

Update the firmware of NETGEAR R7800 routers to the latest version to mitigate the risk of exploitation.

Long-Term Security Practices

Regularly monitor for security updates from NETGEAR and apply them promptly to prevent potential security breaches.

Patching and Updates

Stay informed about patch releases from NETGEAR and promptly apply any security updates to maintain a secure network environment.