CVE-2017-16306 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_exw, at 0x9d01b2ac, the value for the `flg` 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-2017-16306 represents a critical stack-based buffer overflow within the PubNub message handler of Insteon Hub firmware version 1012. This flaw specifically targets the "cc" channel functionality and demonstrates a classic security weakness that has been documented under CWE-121, which addresses stack-based buffer overflow conditions. The vulnerability exists in the command processing logic where the system fails to properly validate input lengths before copying data to fixed-size buffers, creating an exploitable condition that can be leveraged for arbitrary code execution.
The technical implementation of this vulnerability occurs within the cmd sn_exw function at memory address 0x9d01b2ac where the value associated with the 'flg' key is copied using the dangerous strcpy function to a buffer located at stack offset $sp+0x280. This buffer allocation is only 16 bytes in size, making it susceptible to overflow when longer input data is provided. The use of strcpy without proper bounds checking creates a direct pathway for attackers to overwrite adjacent stack memory, potentially including return addresses and other critical program state information. This type of vulnerability aligns with ATT&CK technique T1059.007 for command and script injection, as the overflow can be exploited to execute malicious code within the context of the vulnerable application.
The operational impact of this vulnerability is significant as it allows authenticated remote attackers to exploit the system through legitimate HTTP requests sent via the PubNub messaging service. This means that an attacker with valid credentials or access to the PubNub channel could potentially compromise the entire Insteon Hub device. The vulnerability's exploitation requires minimal prerequisites since it operates over standard HTTP protocols and leverages existing communication channels, making it particularly dangerous in home automation environments where such devices are often deployed with limited security monitoring. The buffer overflow could result in denial of service, arbitrary code execution, or complete system compromise, depending on the attacker's level of access and expertise.
Mitigation strategies for this vulnerability should include immediate firmware updates from Insteon to address the buffer overflow condition, implementing input validation and bounds checking in all string operations, and restricting access to the PubNub channels through authentication and authorization controls. Organizations should also consider network segmentation to limit exposure of such devices to untrusted networks, implement intrusion detection systems to monitor for suspicious PubNub traffic patterns, and establish regular security assessments of IoT devices within their infrastructure. The vulnerability demonstrates the importance of secure coding practices particularly around string handling functions like strcpy and underscores the need for comprehensive security testing of embedded systems before deployment in critical environments.