CVE-2021-27256 Explained : Impact and Mitigation

This article provides detailed information about CVE-2021-27256, a vulnerability that allows network-adjacent attackers to execute arbitrary code on NETGEAR R7800 firmware version 1.0.2.76. Find out the impact, technical details, and mitigation steps associated with this CVE.

Understanding CVE-2021-27256

This section delves into the vulnerability CVE-2021-27256 affecting NETGEAR R7800 routers.

What is CVE-2021-27256?

CVE-2021-27256 allows network-adjacent attackers to run malicious code on NETGEAR R7800 firmware version 1.0.2.76 by exploiting a flaw in handling a specific parameter.

The Impact of CVE-2021-27256

The impact of this vulnerability is rated high, as attackers can execute code with root privileges and bypass authentication mechanisms on affected systems.

Technical Details of CVE-2021-27256

Explore the technical aspects of CVE-2021-27256, including the vulnerability description, affected systems, and exploitation mechanism.

Vulnerability Description

The flaw lies in the inadequate validation of a user-supplied string, allowing attackers to execute system calls and gain root access.

Affected Systems and Versions

NETGEAR R7800 routers running firmware version 1.0.2.76 are affected by CVE-2021-27256.

Exploitation Mechanism

Attackers can exploit the vulnerability by manipulating the rc_service parameter in apply_save.cgi to execute arbitrary code.

Mitigation and Prevention

Discover the necessary steps to mitigate the risks posed by CVE-2021-27256 and prevent potential exploits.

Immediate Steps to Take

Users are advised to update their firmware to the patched version provided by NETGEAR and monitor for any suspicious activities.

Long-Term Security Practices

Implementing network segmentation, strong passwords, and regular security audits can enhance the overall security posture.

Patching and Updates

Regularly check for security updates from NETGEAR and apply them promptly to safeguard against known vulnerabilities.