CVE-2017-16269 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_b, at 0x9d01672c, the value for the `s_speaker` key is copied using `strcpy` to the buffer at `$sp+0x2d0`.This buffer is 100 bytes large, sending anything longer will cause a buffer overflow.
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Analysis
by VulDB Data Team • 02/04/2023
The CVE-2017-16269 vulnerability represents a critical stack-based buffer overflow in the Insteon Hub's PubNub message handler, specifically targeting the "cc" channel functionality. This vulnerability resides within the firmware version 1012 of the Insteon Hub device, which serves as a smart home automation controller connecting various IoT devices through wireless protocols. The flaw manifests in the command processing logic where the system fails to properly validate input length before copying data into a fixed-size buffer, creating an exploitable condition that can be leveraged by remote attackers to execute arbitrary code on the device.
The technical implementation of this vulnerability occurs within the cmd s_b function at memory address 0x9d01672c, where the system processes the `s_speaker` key value from incoming PubNub messages. The buffer allocated for this operation is precisely 100 bytes in size, yet the system employs the unsafe `strcpy` function to copy data from the incoming message without any bounds checking. This primitive copying operation directly overwrites the stack frame, allowing an attacker to manipulate the program's execution flow by overwriting return addresses, saved registers, and other critical stack data. The vulnerability specifically targets the stack pointer offset of $sp+0x2d0, indicating a precise memory layout where the buffer overflow can be systematically exploited to achieve code execution control.
The operational impact of this vulnerability extends beyond simple remote code execution, as it fundamentally compromises the security posture of the entire Insteon Hub ecosystem. An attacker with access to the PubNub service can craft malicious payloads that, when processed by the vulnerable hub, could lead to complete system compromise. The requirement for an authenticated HTTP request indicates that the attack vector involves legitimate communication with the hub's PubNub interface, making the exploitation more plausible in real-world scenarios. This vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a classic example of unsafe string handling in embedded systems. The attack can potentially be leveraged to gain persistent access to the smart home network, enabling further lateral movement and escalation within the connected IoT environment.
Mitigation strategies for CVE-2017-16269 should prioritize immediate firmware updates from Insteon to address the root cause of the buffer overflow vulnerability. Network segmentation and access control measures should be implemented to limit exposure of the Insteon Hub to untrusted networks, while monitoring systems should be deployed to detect anomalous PubNub traffic patterns that might indicate exploitation attempts. The vulnerability demonstrates the importance of input validation and the dangers of using unsafe string manipulation functions like strcpy in security-critical applications, reinforcing principles from the ATT&CK framework's defense evasion techniques. Organizations should also consider implementing network-based intrusion detection systems to monitor for known exploitation signatures and maintain comprehensive incident response procedures to address potential compromise scenarios.