CVE-2019-17519 in NXP
Summary
by MITRE
The Bluetooth Low Energy implementation on NXP SDK through 2.2.1 for KW41Z devices does not properly restrict the Link Layer payload length, allowing attackers in radio range to cause a buffer overflow via a crafted packet.
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Analysis
by VulDB Data Team • 03/30/2024
The vulnerability identified as CVE-2019-17519 affects the Bluetooth Low Energy implementation within NXP SDK versions up to 2.2.1 specifically targeting KW41Z devices. This flaw resides in the Link Layer payload length restriction mechanism, which serves as a critical security control in wireless communication protocols. The improper handling of payload length parameters creates a pathway for malicious actors to exploit buffer management weaknesses in the device's wireless stack. The vulnerability is particularly concerning as it operates at the physical layer of wireless communication, making it accessible to attackers within radio range of the affected devices. This type of vulnerability falls under the category of buffer overflow conditions that can lead to system instability and potential code execution. The affected KW41Z devices are commonly deployed in IoT applications where wireless connectivity is essential for device operation and data transmission. The implementation flaw allows for the injection of malformed packets that exceed normal payload size limits, potentially causing memory corruption in the device's processing unit.
The technical exploitation of this vulnerability occurs when an attacker crafts specific Bluetooth Low Energy packets with oversized payload data that bypasses normal length validation checks within the Link Layer implementation. The system fails to properly validate or restrict the maximum allowed payload length, enabling attackers to send packets that exceed the allocated buffer space. This buffer overflow condition can result in memory corruption that may lead to arbitrary code execution, device crashes, or system instability. The vulnerability demonstrates a clear weakness in input validation and memory management practices within the Bluetooth stack implementation. From a cybersecurity perspective, this represents a significant risk to IoT device security as it allows remote code execution capabilities without requiring physical access to the device. The attack surface is expanded due to the wireless nature of the vulnerability, making it particularly dangerous for devices deployed in uncontrolled environments. This flaw aligns with CWE-121, which describes heap-based buffer overflow conditions, and represents a classic example of improper input validation leading to memory corruption.
The operational impact of CVE-2019-17519 extends beyond simple device disruption to potentially enable full system compromise for affected KW41Z devices. Attackers can leverage this vulnerability to gain unauthorized access to the device's operating system, potentially leading to data exfiltration, device takeover, or use as a pivot point for attacks on connected networks. The vulnerability is particularly dangerous in industrial IoT deployments where these devices may control critical infrastructure components or serve as part of larger security ecosystems. Organizations using NXP KW41Z devices in security-sensitive applications face significant risk exposure, as the vulnerability can be exploited without requiring specialized equipment or deep technical knowledge. The attack can be executed from distances ranging from a few meters to several hundred meters depending on the wireless environment and device specifications. This vulnerability affects the fundamental security posture of wireless IoT deployments and represents a critical weakness in the device's defensive architecture. The potential for persistent compromise increases when devices remain exposed to the wireless attack surface without proper mitigation measures.
Mitigation strategies for CVE-2019-17519 should focus on immediate firmware updates from NXP to address the payload length validation flaw in the Bluetooth Low Energy implementation. Organizations must prioritize the deployment of security patches to all affected KW41Z devices within their inventory, particularly those deployed in critical or sensitive environments. Network segmentation and monitoring of wireless traffic can provide additional layers of defense by detecting anomalous packet patterns that may indicate exploitation attempts. Implementing proper wireless access controls and device authentication mechanisms can help reduce the attack surface available to potential adversaries. Security teams should conduct comprehensive inventory assessments to identify all affected devices and establish monitoring procedures for detecting unauthorized wireless activity. The vulnerability highlights the importance of maintaining up-to-date firmware and security patches in IoT deployments, as it demonstrates how outdated implementations can create persistent security risks. Organizations should also consider implementing intrusion detection systems specifically designed to monitor for Bluetooth Low Energy anomalies and payload irregularities. Regular security assessments and penetration testing of wireless networks can help identify similar vulnerabilities in other components of the IoT ecosystem. This vulnerability serves as a reminder of the critical need for robust input validation and memory management practices in embedded systems and wireless communication protocols.