CVE-2018-3896 Explained : Impact and Mitigation

A security flaw in the Samsung SmartThings Hub with Firmware version 0.20.17 allows for buffer overflow vulnerabilities to be exploited through the video-core's HTTP server.

Understanding CVE-2018-3896

The vulnerability in the /cameras/XXXX/clips handler of the video-core's HTTP server in the Samsung SmartThings Hub with Firmware version 0.20.17 poses a critical security risk.

What is CVE-2018-3896?

The flaw in the /cameras/XXXX/clips handler of the video-core's HTTP server in the Samsung SmartThings Hub with Firmware version 0.20.17 enables buffer overflow vulnerabilities to be exploited by manipulating a user-controlled JSON payload.

The Impact of CVE-2018-3896

The vulnerability has a CVSS base score of 9.9, indicating a critical severity level with high impacts on confidentiality, integrity, and availability of the affected system.

Technical Details of CVE-2018-3896

The technical aspects of the CVE-2018-3896 vulnerability provide insights into its nature and potential risks.

Vulnerability Description

The flaw arises from the video-core process improperly handling data from a user-controlled JSON payload, leading to a buffer overflow on the stack.
The buffer overflow occurs due to the strncpy call overflowing the destination buffer, which is limited to 52 bytes.
An attacker can exploit this vulnerability by sending a "correlationId" value of any length.

Affected Systems and Versions

Product: SmartThings Hub STH-ETH-250
Vendor: Samsung
Firmware version: 0.20.17

Exploitation Mechanism

Attack Complexity: Low
Attack Vector: Network
Privileges Required: Low
User Interaction: None
Scope: Changed
The attacker can exploit the vulnerability remotely without user interaction, making it a critical threat.

Mitigation and Prevention

Protecting systems from CVE-2018-3896 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update the firmware of the Samsung SmartThings Hub to a secure version that addresses the buffer overflow vulnerability.
Monitor network traffic for any suspicious activities that could indicate an ongoing exploitation attempt.

Long-Term Security Practices

Implement network segmentation to isolate critical devices from potential attackers.
Regularly review and update security configurations to mitigate future vulnerabilities.

Patching and Updates

Stay informed about security updates and patches released by Samsung for the SmartThings Hub to address known vulnerabilities and enhance system security.