CVE-2017-11120 in tvOS
Summary
by MITRE
On Broadcom BCM4355C0 Wi-Fi chips 9.44.78.27.0.1.56 and other chips, an attacker can craft a malformed RRM neighbor report frame to trigger an internal buffer overflow in the Wi-Fi firmware, aka B-V2017061204.
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Analysis
by VulDB Data Team • 11/10/2024
The vulnerability identified as CVE-2017-11120 affects Broadcom BCM4355C0 Wi-Fi chips and other similar devices running firmware version 9.44.78.27.0.1.56 or related variants. This represents a critical buffer overflow condition within the wireless firmware that can be exploited through carefully crafted network packets. The issue stems from insufficient input validation in the RRM neighbor report frame processing functionality, which is part of the IEEE 802.11 standard for radio resource management. This vulnerability falls under the CWE-121 buffer overflow category, specifically manifesting as a stack-based buffer overflow that can be triggered by malformed wireless frames transmitted over the air.
The technical exploitation of this vulnerability occurs when a malicious actor transmits a specially crafted RRM neighbor report frame to a targeted device running the vulnerable Broadcom Wi-Fi chip. The firmware fails to properly validate the length and structure of the incoming frame data, allowing an attacker to overwrite adjacent memory locations within the device's firmware execution environment. This buffer overflow condition can potentially lead to arbitrary code execution within the Wi-Fi chip's firmware context, effectively compromising the device's wireless functionality. The attack vector requires only wireless network access and does not necessitate physical proximity or authentication credentials, making it particularly concerning for enterprise and consumer devices alike.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it creates potential for complete device compromise and persistent backdoor access. When successfully exploited, the buffer overflow can cause the Wi-Fi chip to crash or behave unpredictably, potentially leading to complete wireless connectivity loss. More critically, the arbitrary code execution capability allows attackers to gain persistent control over the device's wireless capabilities, enabling them to monitor network traffic, inject malicious frames, or even use the compromised device as a pivot point for attacking other networked systems. This vulnerability directly maps to ATT&CK technique T1059.007 for command and control through wireless protocols and T1566 for credential access through wireless network exploitation.
Mitigation strategies for this vulnerability require immediate firmware updates from Broadcom and device manufacturers, as the issue affects multiple generations of Wi-Fi chipsets. Network administrators should implement wireless intrusion detection systems to monitor for suspicious RRM neighbor report frames and consider temporary network segmentation to limit the potential impact of exploitation. Device vendors must ensure proper input validation and bounds checking in all wireless firmware components, particularly those handling IEEE 802.11 management frames. The vulnerability demonstrates the critical importance of robust firmware security practices and highlights the need for regular security assessments of embedded wireless components. Organizations should also implement network monitoring solutions that can detect anomalous wireless traffic patterns indicative of buffer overflow exploitation attempts. Given the widespread deployment of affected Broadcom chips in consumer devices, IoT networks, and enterprise infrastructure, this vulnerability represents a significant risk requiring immediate attention and remediation.