CVE-2021-45991 Explained : Impact and Mitigation

Tenda routers G1 and G3 v15.11.0.17(9502)_CN have been found to have a stack overflow vulnerability in the function formAddVpnUsers, enabling attackers to execute a Denial of Service (DoS) attack using the vpnUsers parameter.

Understanding CVE-2021-45991

This CVE involves a vulnerability in Tenda routers G1 and G3 that allows for a DoS attack.

What is CVE-2021-45991?

The vulnerability in Tenda routers G1 and G3 v15.11.0.17(9502)_CN permits attackers to perform a DoS attack through the vpnUsers parameter.

The Impact of CVE-2021-45991

This vulnerability exposes Tenda routers to the risk of DoS attacks, potentially disrupting network services for users.

Technical Details of CVE-2021-45991

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The vulnerability lies in the stack overflow in the formAddVpnUsers function of Tenda routers G1 and G3.

Affected Systems and Versions

Product: Tenda routers G1 and G3
Vendor: Tenda
Version: v15.11.0.17(9502)_CN

Exploitation Mechanism

Attackers can exploit this vulnerability by manipulating the vpnUsers parameter, leading to a DoS condition.

Mitigation and Prevention

Taking security measures is crucial to safeguard systems against this vulnerability.

Immediate Steps to Take

Disable remote management on the affected routers if not required.
Implement network segmentation to isolate critical devices.
Monitor network traffic for any suspicious activity.

Long-Term Security Practices

Keep router firmware up to date with the latest patches.
Regularly review and update router configurations to enhance security.

Patching and Updates

Apply patches and firmware updates provided by Tenda to address the vulnerability.