CVE-2021-31756 Explained : Impact and Mitigation

This article delves into the details of CVE-2021-31756, a vulnerability found in Tenda AC11 devices with firmware through 02.03.01.104_CN, allowing attackers to execute arbitrary code on the system.

Understanding CVE-2021-31756

This section will cover what CVE-2021-31756 is, its impact, technical details, and mitigation strategies.

What is CVE-2021-31756?

CVE-2021-31756 is a stack buffer overflow vulnerability discovered in Tenda AC11 devices. Attackers can exploit this flaw through a crafted post request to execute malicious code on the system.

The Impact of CVE-2021-31756

The impact of this vulnerability is severe as it enables threat actors to gain unauthorized access to affected devices and execute arbitrary code, posing a serious security risk to users.

Technical Details of CVE-2021-31756

This section will provide more insights into the vulnerability, including its description, affected systems, versions, and the exploitation mechanism.

Vulnerability Description

The stack buffer overflow vulnerability in /gofrom/setwanType allows attackers to control the input vector, leading to an arbitrary code execution due to a buffer overflow.

Affected Systems and Versions

Tenda AC11 devices with firmware through version 02.03.01.104_CN are susceptible to this vulnerability.

Exploitation Mechanism

Attackers exploit this vulnerability by sending a specially crafted post request containing malicious data to trigger the buffer overflow and execute arbitrary code.

Mitigation and Prevention

Protecting against CVE-2021-31756 requires immediate steps and long-term security practices to safeguard devices from potential attacks.

Immediate Steps to Take

Users should update their Tenda AC11 devices to the latest firmware version provided by the vendor to patch the vulnerability and prevent exploitation.

Long-Term Security Practices

Implementing network segmentation, using intrusion detection systems, and regularly updating firmware are essential security practices to prevent future vulnerabilities.

Patching and Updates

Regularly checking for firmware updates from Tenda and promptly applying patches is crucial to mitigate the risk of exploitation.