CVE-2020-8962 : Vulnerability Insights and Analysis

A stack-based buffer overflow vulnerability was discovered on the D-Link DIR-842 REVC with firmware v3.13B09 HOTFIX due to improper handling of POST requests.

Understanding CVE-2020-8962

This CVE involves a critical buffer overflow issue on specific D-Link router firmware versions.

What is CVE-2020-8962?

A stack-based buffer overflow was identified on the D-Link DIR-842 REVC router firmware v3.13B09 HOTFIX, triggered by the use of strcpy for LOGINPASSWORD during POST request processing.

The Impact of CVE-2020-8962

The vulnerability could allow remote attackers to execute arbitrary code or crash the device, potentially leading to a denial of service (DoS) condition.

Technical Details of CVE-2020-8962

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The issue arises from a stack-based buffer overflow in the router's handling of POST requests to the /MTFWU endpoint, caused by the use of the vulnerable strcpy function.

Affected Systems and Versions

Product: D-Link DIR-842 REVC
Firmware Version: v3.13B09 HOTFIX

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specially crafted POST requests to the /MTFWU endpoint, leading to a buffer overflow and potential code execution.

Mitigation and Prevention

Protecting systems from CVE-2020-8962 requires immediate actions and long-term security measures.

Immediate Steps to Take

Disable remote access if not required
Implement network segmentation to limit exposure
Apply firewall rules to restrict access to vulnerable services

Long-Term Security Practices

Regularly update firmware to the latest version
Conduct security assessments and penetration testing
Educate users on secure password practices

Patching and Updates

Check for firmware updates from D-Link and apply patches promptly to mitigate the vulnerability.