CVE-2022-40855 : What You Need to Know

The Tenda W20E router V15.11.0.6 is impacted by a stack overflow vulnerability in the function formSetPortMapping. This flaw exists in the post request 'goform/setPortMapping/' and can result in a Denial of Service (DoS) or Remote Code Execution (RCE) through specific parameters.

Understanding CVE-2022-40855

This section provides insights into the nature and implications of the CVE-2022-40855 vulnerability.

What is CVE-2022-40855?

The CVE-2022-40855 vulnerability affects the Tenda W20E router V15.11.0.6, allowing threat actors to exploit a stack overflow in the formSetPortMapping function via specific post request parameters.

The Impact of CVE-2022-40855

The presence of this vulnerability poses a significant risk as attackers can potentially execute a Denial of Service attack or achieve Remote Code Execution, compromising the security and functionality of the affected device.

Technical Details of CVE-2022-40855

This section delves into the technical aspects of the CVE-2022-40855 vulnerability.

Vulnerability Description

The vulnerability resides in the formSetPortMapping function of the Tenda W20E router, triggered by specific post request parameters. This flaw leads to a stack overflow, enabling malicious actors to disrupt services or execute arbitrary code.

Affected Systems and Versions

The CVE-2022-40855 vulnerability impacts the Tenda W20E router running version V15.11.0.6. Users with this particular router version are at risk of exploitation if adequate mitigations are not implemented.

Exploitation Mechanism

By sending crafted requests to the 'goform/setPortMapping/' resource with malicious values for portMappingServer, portMappingProtocol, portMappingWan, porMappingtInternal, and portMappingExternal parameters, threat actors can trigger the stack overflow and carry out DoS or RCE attacks.

Mitigation and Prevention

Explore the steps to address and prevent the CVE-2022-40855 vulnerability.

Immediate Steps to Take

Users of the Tenda W20E router V15.11.0.6 should immediately update to a patched version provided by the vendor. Additionally, network segmentation and access controls can help reduce the attack surface.

Long-Term Security Practices

To enhance overall security posture, it's crucial to implement regular security updates, conduct security training for users, and perform periodic security assessments of network devices.

Patching and Updates

Regularly check for official security updates from Tenda and apply patches promptly to mitigate the risk of exploitation.