CVE-2021-45996 Explained : Impact and Mitigation

Tenda routers G1 and G3 v15.11.0.17(9502)_CN were discovered to contain a stack overflow vulnerability that allows attackers to launch Denial of Service attacks through specific parameters.

Understanding CVE-2021-45996

The vulnerability in Tenda routers G1 and G3 can lead to a Denial of Service (DoS) attack by exploiting certain parameters.

What is CVE-2021-45996?

The CVE-2021-45996 vulnerability arises from a stack overflow in the function formSetPortMapping in Tenda routers G1 and G3, potentially enabling attackers to execute DoS attacks.

The Impact of CVE-2021-45996

This vulnerability can be exploited by malicious actors to disrupt services on affected Tenda routers, leading to denial of service incidents.

Technical Details of CVE-2021-45996

The technical aspects of the CVE-2021-45996 vulnerability are as follows:

Vulnerability Description

The vulnerability allows attackers to trigger a stack overflow using specific parameters in the routers, resulting in a DoS condition.

Affected Systems and Versions

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

Exploitation Mechanism

Attackers can exploit the vulnerability by manipulating parameters like portMappingServer, portMappingProtocol, portMappingWan, porMappingtInternal, and portMappingExternal in the affected Tenda routers.

Mitigation and Prevention

To address CVE-2021-45996, consider the following steps:

Immediate Steps to Take

Disable remote access to the router's web interface.
Monitor network traffic for any suspicious activities targeting port mapping parameters.

Long-Term Security Practices

Regularly update router firmware to the latest version.
Implement network firewall rules to filter and block malicious traffic.

Patching and Updates

Stay informed about security advisories from Tenda and apply patches promptly to mitigate the risk posed by the CVE-2021-45996 vulnerability.