CVE-2018-3867 in SmartThings Hub STH-ETH-250
Summary
by MITRE
An exploitable stack-based buffer overflow vulnerability exists in the samsungWifiScan callback notification of video-core's HTTP server of Samsung SmartThings Hub STH-ETH-250 devices with firmware version 0.20.17. The video-core process incorrectly handles the answer received from a smart camera, leading to a buffer overflow on the stack. An attacker can send a series of HTTP requests to trigger this vulnerability.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 05/04/2023
The vulnerability identified as CVE-2018-3867 represents a critical stack-based buffer overflow within the Samsung SmartThings Hub STH-ETH-250 device firmware version 0.20.17. This issue resides in the video-core component's HTTP server implementation where the samsungWifiScan callback notification mechanism fails to properly validate input data received from smart cameras. The flaw manifests when the video-core process handles responses from connected smart cameras, specifically during the processing of network communication between the hub and camera devices. The buffer overflow occurs on the stack memory allocation, creating a potential execution path for malicious actors to gain unauthorized access to the device's operating system.
The technical exploitation of this vulnerability follows a well-defined pattern that aligns with common stack overflow attack vectors. The flaw stems from inadequate bounds checking within the video-core process when processing HTTP responses from smart cameras. The samsungWifiScan callback function does not properly validate the size or content of incoming data, allowing an attacker to craft specifically formatted HTTP responses that exceed the allocated stack buffer space. This condition creates a classic stack-based buffer overflow scenario where malicious data can overwrite adjacent memory locations including return addresses and control registers. The vulnerability is particularly concerning as it operates within the HTTP server context, meaning that remote attackers can trigger the condition through network-based HTTP requests without requiring physical access to the device.
From an operational perspective, this vulnerability presents significant security implications for users of Samsung SmartThings Hub devices, particularly in environments where network security is not adequately enforced. The attack surface extends beyond simple device compromise to include potential lateral movement within home or enterprise networks where the hub serves as a central communication point for multiple IoT devices. The vulnerability affects the core functionality of the SmartThings ecosystem, potentially allowing attackers to execute arbitrary code on the device, modify network configurations, or establish persistent access points within the local network. According to CWE classification, this represents a CWE-121: Stack-based Buffer Overflow, which is categorized under the broader category of CWE-119: Improper Access of Resource Using Buffer Index, making it a direct threat to system integrity and availability.
The attack vector for this vulnerability is particularly dangerous as it requires minimal privileges and can be executed remotely over the network. An attacker needs only to send a series of specially crafted HTTP requests to the device's HTTP server to trigger the buffer overflow condition. This approach aligns with ATT&CK framework tactic TA0001: Initial Access, specifically technique T1190: Exploit Public-Facing Application, where adversaries leverage vulnerabilities in publicly accessible services to gain entry. The exploitation process demonstrates the common pattern of network-based attacks targeting web server components, where the attacker crafts malicious input to overflow buffer space and subsequently manipulate program execution flow. The impact extends beyond immediate device compromise to include potential data exfiltration and network reconnaissance activities that could be leveraged for more extensive attacks.
Mitigation strategies for CVE-2018-3867 should focus on both immediate remediation and long-term security improvements. The primary recommendation involves firmware updates from Samsung to address the specific buffer overflow condition within the video-core HTTP server implementation. Organizations should also implement network segmentation and access controls to limit exposure of SmartThings hubs to untrusted networks. Additional defensive measures include deploying network monitoring solutions to detect anomalous HTTP traffic patterns that might indicate exploitation attempts, implementing proper input validation at network boundaries, and establishing regular firmware update policies for IoT devices. The vulnerability highlights the importance of secure coding practices and input validation in embedded systems, particularly those serving as central hubs in home automation ecosystems where device security directly impacts overall network security posture.