CVE-2018-3879 in SmartThings Hub STH-ETH-250
Summary
by MITRE
An exploitable JSON injection vulnerability exists in the credentials handler 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 parses the user-controlled JSON payload, leading to a JSON injection which in turn leads to a SQL injection in the video-core database. An attacker can send a series of HTTP requests to trigger this vulnerability.
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Analysis
by VulDB Data Team • 05/04/2023
The CVE-2018-3879 vulnerability represents a critical security flaw in Samsung SmartThings Hub STH-ETH-250 devices running firmware version 0.20.17. This vulnerability resides within the video-core HTTP server component that handles credential management operations, making it particularly dangerous as it directly impacts the device's authentication and authorization mechanisms. The flaw stems from inadequate input validation and sanitization within the JSON parsing logic, creating a chain of security failures that can be exploited by remote attackers to gain unauthorized access to sensitive system resources.
The technical exploitation of this vulnerability begins with a JSON injection attack that targets the credentials handler of the video-core process. When the system receives user-controlled JSON payloads through HTTP requests, it fails to properly validate or sanitize the input data before processing. This improper handling creates a pathway for attackers to inject malicious JSON content that can manipulate the parsing behavior of the video-core application. The vulnerability is classified as a CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component, specifically manifesting as a CWE-94 Code Injection in the context of JSON parsing. The flaw operates at the application layer where the JSON parser does not adequately distinguish between legitimate data and maliciously crafted injection payloads.
The operational impact of this vulnerability extends beyond simple data manipulation to create a full SQL injection attack vector that can compromise the underlying database of the video-core system. When the malformed JSON payload is processed, it allows attackers to inject SQL commands directly into the database queries, potentially enabling data exfiltration, unauthorized database modifications, or complete system compromise. The vulnerability requires only a series of HTTP requests to be triggered, making it highly exploitable and suitable for automated attack scenarios. This characteristic places the vulnerability in the ATT&CK matrix under T1071.004 Application Layer Protocol: DNS and T1190 Exploit Public-Facing Application, highlighting its accessibility and the potential for widespread impact across multiple devices.
The security implications of this vulnerability are particularly severe given that SmartThings Hub devices serve as central control points for home automation systems, often containing sensitive information about user environments, device configurations, and potentially personal data. Attackers who successfully exploit this vulnerability could gain access to the complete database of video-core credentials, potentially allowing them to escalate privileges and access additional system resources. The lack of proper input validation in the JSON parsing process creates a fundamental security weakness that violates the principle of least privilege and proper data sanitization. Organizations should consider implementing network segmentation and monitoring for unusual HTTP traffic patterns to detect potential exploitation attempts. The vulnerability underscores the critical importance of robust input validation and sanitization in all components handling user-supplied data, particularly in embedded systems where security updates may be limited or difficult to deploy.