CVE-2017-16253 in Hub 2245-222
Summary
by MITRE
An exploitable buffer overflow vulnerability exists in the PubNub message handler Insteon Hub 2245-222 - Firmware version 1012 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 can send an authenticated HTTP request At 0x9d014dd8 the value for the id key is copied using strcpy to the buffer at $sp+0x290. This buffer is 32 bytes large, sending anything longer will cause a buffer overflow.
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Analysis
by VulDB Data Team • 08/03/2023
The vulnerability described in CVE-2017-16253 represents a critical stack-based buffer overflow flaw within the PubNub message handler component of the Insteon Hub 2245-222 device running firmware version 1012. This issue specifically affects the cc channel functionality and demonstrates a classic programming error where unbounded string copying operations are employed without proper bounds checking. The vulnerability resides in the device's web server implementation that processes messages received through the PubNub messaging service, creating an attack surface that can be exploited by remote authenticated adversaries. The flaw is particularly concerning as it allows attackers to manipulate the device's memory layout and potentially execute arbitrary code, given the nature of stack-based buffer overflows and their ability to overwrite critical program control data.
The technical implementation of this vulnerability stems from the improper use of the strcpy function when handling the id key parameter within HTTP requests. The system allocates a 32-byte buffer at stack location $sp+0x290 to store the incoming identifier value, yet fails to validate the length of the input data before copying. When an attacker sends a crafted HTTP request containing an id value longer than 32 bytes, the strcpy operation continues copying beyond the allocated buffer boundaries, overwriting adjacent stack memory locations. This memory corruption can affect return addresses, function pointers, and other critical control data, potentially allowing attackers to redirect program execution flow. The specific memory address 0x9d014dd8 mentioned in the vulnerability description indicates the location where the id value is processed and copied, making this attack vector highly predictable and exploitable for remote code execution.
The operational impact of this vulnerability extends beyond simple denial of service conditions to encompass full system compromise capabilities. An authenticated attacker with access to the device's HTTP interface can leverage this flaw to execute arbitrary commands on the affected Insteon Hub, potentially gaining complete control over the home automation system. This compromise could enable attackers to manipulate connected devices, access sensitive user data, or establish persistent access points within the network infrastructure. The vulnerability affects not only the device's immediate functionality but also poses risks to the broader home network security, as the Insteon Hub often serves as a central control point for multiple connected devices. The attack requires minimal privileges since it only needs authenticated HTTP access, making it particularly dangerous in environments where device credentials might be compromised or weak authentication mechanisms are in place.
Mitigation strategies for this vulnerability should focus on immediate firmware updates provided by the vendor, which would include proper bounds checking and input validation mechanisms. The implementation should replace vulnerable strcpy operations with safer alternatives such as strncpy or strlcpy functions that enforce maximum buffer limits. Network segmentation and access control measures should be implemented to limit exposure of the device to untrusted networks, while authentication mechanisms should be strengthened to prevent unauthorized access. Security monitoring should be enhanced to detect anomalous HTTP request patterns that might indicate exploitation attempts. This vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which is classified under the broader category of CWE-119 Improper Access to Memory, and maps to ATT&CK technique T1059 Command and Scripting Interpreter for remote code execution. Organizations should also consider implementing network intrusion detection systems that can identify and block suspicious PubNub messaging patterns targeting this specific vulnerability. The remediation process requires careful attention to ensure that all instances of vulnerable string handling functions are identified and replaced throughout the firmware codebase, as similar issues may exist in other components of the device's software stack.