CVE-2017-16293 in Insteon
Summary
by MITRE • 01/12/2023
Multiple exploitable buffer overflow vulnerabilities exist in the PubNub message handler for the "cc" channel of Insteon Hub running firmware version 1012. Specially crafted commands sent through the PubNub service can cause a stack-based buffer overflow overwriting arbitrary data. An attacker should send an authenticated HTTP request to trigger this vulnerability. In cmd s_schd, at 0x9d01a010, the value for the `grp` key is copied using `strcpy` to the buffer at `$sp+0x280`.This buffer is 16 bytes large, sending anything longer will cause a buffer overflow.
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Analysis
by VulDB Data Team • 02/04/2023
The vulnerability described in CVE-2017-16293 represents a critical stack-based buffer overflow flaw within the Insteon Hub's PubNub message handling system. This vulnerability specifically targets the "cc" channel functionality of the device's firmware version 1012, creating a dangerous condition where maliciously crafted input can overwrite adjacent memory locations. The flaw exists in the command processing logic where unvalidated input from the PubNub service is directly copied into a fixed-size buffer without proper bounds checking, making it susceptible to exploitation by remote attackers who can manipulate the system's memory layout. The vulnerability operates through the cmd s_schd function at memory address 0x9d01a010, where the group identifier value from the `grp` key is copied using the unsafe strcpy function, which does not perform any length validation against the destination buffer.
The technical implementation of this vulnerability demonstrates a classic buffer overflow pattern where the destination buffer at stack location $sp+0x280 is only 16 bytes in size, while the input data from the `grp` key can exceed this limit. This design flaw directly maps to CWE-121, which categorizes stack-based buffer overflow conditions, and specifically aligns with CWE-676, indicating the use of dangerous functions like strcpy that can lead to memory corruption. The vulnerability requires an authenticated HTTP request to trigger, meaning that an attacker must first establish valid credentials to access the Insteon Hub's administrative interface, but once achieved, the buffer overflow can potentially be exploited to execute arbitrary code or cause system instability. The attack vector leverages the PubNub messaging service as an intermediary, allowing remote exploitation through the device's legitimate communication channels, which creates a sophisticated attack scenario where the attacker can manipulate the system's execution flow by overwriting return addresses or other critical stack data.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as the buffer overflow could potentially allow for remote code execution or privilege escalation within the Insteon Hub's operating environment. The device's role as a home automation hub makes this particularly concerning since it controls various connected devices and systems, potentially allowing attackers to gain unauthorized access to the home network or manipulate connected appliances. The vulnerability's exploitation could result in complete system compromise, data exfiltration, or disruption of critical home automation services, affecting not just the device itself but the broader connected ecosystem it manages. This scenario aligns with ATT&CK technique T1059, which covers command and scripting interpreter usage, as successful exploitation could enable attackers to execute malicious commands within the device's environment.
Mitigation strategies for this vulnerability should focus on immediate firmware updates from the manufacturer, as the most effective solution requires addressing the root cause through proper input validation and buffer management. Organizations should implement network segmentation to limit access to the Insteon Hub's administrative interfaces, restricting access to only authorized personnel and systems. Additionally, network monitoring should be enhanced to detect unusual PubNub traffic patterns or unauthorized HTTP requests that might indicate exploitation attempts. The implementation of input sanitization measures, including the replacement of unsafe functions like strcpy with safer alternatives such as strncpy, should be mandatory for any custom code handling user input. Security teams should also consider implementing intrusion detection systems that can identify and alert on buffer overflow patterns or memory corruption attempts. The vulnerability highlights the importance of secure coding practices and input validation, particularly in embedded systems where resource constraints may lead to the use of unsafe functions without proper bounds checking, emphasizing the need for comprehensive security reviews during the development lifecycle to prevent similar issues from emerging in future implementations.