CVE-2017-16257 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 sn_sx, at 0x9d014f28, the value for the `cmd3` key is copied using `strcpy` to the buffer at `$sp+0x2b0`.This buffer is 32 bytes large, sending anything longer will cause a buffer overflow.
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Analysis
by VulDB Data Team • 02/04/2023
The CVE-2017-16257 vulnerability represents a critical stack-based buffer overflow in the Insteon Hub's PubNub message handler implementation. This flaw exists within the firmware version 1012 of the Insteon Hub device, which serves as a central hub for home automation systems connecting various smart home devices. The vulnerability specifically targets the "cc" channel within the PubNub messaging service integration, creating a dangerous attack surface that could allow remote exploitation of the device. The flaw stems from improper input validation and unsafe string handling practices within the device's communication stack, making it particularly concerning for IoT security.
The technical implementation of this vulnerability occurs in the sn_sx function at memory address 0x9d014f28 where the system processes commands received through the PubNub service. When an attacker crafts a malicious HTTP request containing a specially formatted payload with the `cmd3` key, the system directly copies this data into a stack buffer located at `$sp+0x2b0` using the insecure `strcpy` function. This buffer has a fixed size of only 32 bytes, making it trivial for an attacker to exceed this limit and overwrite adjacent stack memory. The use of `strcpy` without bounds checking creates a classic buffer overflow condition that can be exploited to manipulate program execution flow and potentially achieve arbitrary code execution.
The operational impact of this vulnerability extends beyond simple denial of service, as it provides attackers with a pathway for remote code execution on the Insteon Hub device. Since the vulnerability requires an authenticated HTTP request to trigger, it suggests that attackers would need to obtain valid credentials or exploit additional weaknesses to gain access to the device's administrative interface. However, once exploited, the buffer overflow could allow attackers to overwrite return addresses, function pointers, or other critical stack variables, potentially enabling complete system compromise. This represents a significant threat to home automation networks where the Insteon Hub serves as a central control point for multiple connected devices.
Security practitioners should implement immediate mitigations including firmware updates from Insteon to address the buffer overflow vulnerability, network segmentation to limit access to the device, and monitoring for unusual PubNub traffic patterns. The vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which is classified under the broader category of CWE-119 Improper Access of Resource Using Buffer. From an attack perspective, this vulnerability would map to ATT&CK technique T1059 Command and Scripting Interpreter and T1072 Software Deployment Tools, as it enables persistent command execution on the compromised device. Organizations should also consider implementing network access controls to restrict communication with the PubNub service and monitor for potential exploitation attempts that could indicate active attacks against the Insteon Hub infrastructure.