CVE-2021-27708 : Security Advisory and Response

Command Injection vulnerability in TOTOLINK X5000R and A720R routers allows remote attackers to execute arbitrary commands by sending a modified HTTP request.

Understanding CVE-2021-27708

This CVE identifies a critical vulnerability in TOTOLINK routers, enabling attackers to run unauthorized OS commands through a manipulated HTTP request.

What is CVE-2021-27708?

The vulnerability in TOTOLINK X5000R and A720R routers permits threat actors to execute malicious commands on affected devices by exploiting the glibc system function.

The Impact of CVE-2021-27708

Remote attackers can take control of the routers' operating systems, compromising the device's security and potentially leading to unauthorized system access.

Technical Details of CVE-2021-27708

The following details provide insights into the technical aspects of this CVE:

Vulnerability Description

The flaw occurs due to executing the system function with untrusted input, allowing attackers to manipulate the 'command' parameter and compromise the OS security.

Affected Systems and Versions

Devices running TOTOLINK X5000R firmware v9.1.0u.6118_B20201102 and TOTOLINK A720R firmware v4.1.5cu.470_B20200911 are impacted by this vulnerability.

Exploitation Mechanism

By sending a crafted HTTP request, threat actors can inject arbitrary commands into the routers, leveraging direct access to the 'command' field to launch OS attacks.

Mitigation and Prevention

To safeguard against CVE-2021-27708, users and administrators should take the following preventive measures:

Immediate Steps to Take

Disable remote access to affected routers wherever possible
Implement strong firewall rules to restrict unauthorized access

Long-Term Security Practices

Regularly update router firmware to the latest secure versions
Employ network intrusion detection systems to monitor for suspicious activities

Patching and Updates

Refer to TOTOLINK's official security advisories and apply patches promptly to address the vulnerability.