CVE-2018-3866 Explained : Impact and Mitigation

A vulnerability in the samsungWifiScan handler of the HTTP server in the Samsung SmartThings Hub STH-ETH-250 with Firmware version 0.20.17 allows for a buffer overflow, potentially leading to a critical security breach.

Understanding CVE-2018-3866

This CVE involves a buffer overflow vulnerability in the Samsung SmartThings Hub STH-ETH-250 with Firmware version 0.20.17.

What is CVE-2018-3866?

The vulnerability arises from a buffer overflow in the video-core process due to mishandling of user-controlled JSON payloads.
Attackers can exploit this by sending a 'callbackUrl' value of arbitrary length, triggering a stack buffer overflow.

The Impact of CVE-2018-3866

CVSS Score: 9.9 (Critical)
Severity: High impact on confidentiality, integrity, and availability of affected systems.
Attack Vector: Network
Privileges Required: Low
Scope: Changed
User Interaction: None

Technical Details of CVE-2018-3866

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The vulnerability stems from a buffer overflow in the samsungWifiScan handler of the HTTP server.
It occurs during the strcpy operation at position [8], exceeding the intended buffer size.

Affected Systems and Versions

Affected Product: Samsung SmartThings Hub STH-ETH-250
Affected Firmware Version: 0.20.17

Exploitation Mechanism

Exploitation involves sending a 'callbackUrl' value of arbitrary length to trigger the buffer overflow.

Mitigation and Prevention

Protecting systems from CVE-2018-3866 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update the firmware to a patched version that addresses the buffer overflow vulnerability.
Implement network segmentation to limit the impact of potential attacks.

Long-Term Security Practices

Regularly monitor and audit network traffic for any suspicious activities.
Educate users on safe practices to prevent social engineering attacks.

Patching and Updates

Stay informed about security updates and patches released by Samsung for the SmartThings Hub STH-ETH-250.