CVE-2019-9419 in Android
Summary
by MITRE
In Bluetooth, there is a possible out of bounds read due to a missing bounds check. This could lead to remote information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation. Product: AndroidVersions: Android-10Android ID: A-111407544
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Analysis
by VulDB Data Team • 09/13/2020
The vulnerability identified as CVE-2019-9419 represents a critical out-of-bounds read flaw within the Bluetooth implementation of Android 10 operating systems. This security weakness stems from a fundamental missing bounds check in the Bluetooth protocol handling code, specifically affecting the Bluetooth stack's processing of incoming packets or data structures. The vulnerability exists at the kernel level within the Bluetooth subsystem, where insufficient validation occurs before accessing memory regions that could be manipulated by remote attackers. The absence of proper bounds checking allows malicious actors to craft specially formatted Bluetooth packets that trigger memory access violations, potentially leading to information disclosure from adjacent memory locations.
The technical nature of this vulnerability places it squarely within the CWE-129 category of "Improper Validation of Array Index" and more specifically aligns with CWE-125 "Out-of-Bounds Read" as defined by the Common Weakness Enumeration catalog. This flaw operates at the intersection of network protocol processing and memory safety mechanisms, where the Bluetooth stack fails to validate the size or boundaries of incoming data before attempting to read from memory locations. The vulnerability's remote exploitation capability means that attackers do not require physical access or user interaction to exploit the flaw, making it particularly dangerous in environments where Bluetooth devices are frequently connected or where devices are in proximity to potential attackers. The attack vector leverages the inherent trust placed in Bluetooth communication protocols, where devices automatically process incoming connections and data without sufficient validation.
From an operational impact perspective, this vulnerability poses significant risks to Android 10 devices since it enables remote information disclosure without requiring any additional privileges or user interaction. The lack of user interaction requirements means that malicious actors can exploit this vulnerability simply by broadcasting specially crafted Bluetooth signals within range of affected devices. The information disclosure aspect could potentially expose sensitive data such as memory contents, cryptographic keys, or other confidential information stored in adjacent memory regions. This makes the vulnerability particularly concerning for devices that handle sensitive communications or operate in environments where unauthorized access to device memory could lead to broader security compromises. The vulnerability affects all Android 10 devices that implement Bluetooth functionality, creating a widespread impact across various device types including smartphones, tablets, and IoT devices that rely on Bluetooth connectivity.
The mitigation strategies for CVE-2019-9419 primarily involve applying the official security patches released by Google as part of the Android security updates. Organizations should prioritize immediate deployment of the relevant security updates to address the underlying bounds checking deficiency in the Bluetooth stack. System administrators should also consider implementing network segmentation and Bluetooth disabling policies for devices that do not require wireless connectivity, particularly in high-security environments. Monitoring for anomalous Bluetooth activity and implementing intrusion detection systems that can identify suspicious Bluetooth packet patterns may provide additional defensive layers. The vulnerability's classification under the ATT&CK framework would place it within the T1059.007 technique category for "Command and Scripting Interpreter: Python" if exploited through scripting interfaces, though more accurately it aligns with T1046 "Network Service Scanning' and T1056.001 'Input Capture: Keylogging' as potential exploitation methods for information gathering. Organizations should also consider implementing Bluetooth device whitelisting policies and disabling unnecessary Bluetooth services to reduce the attack surface. The vulnerability underscores the importance of proper input validation and memory safety practices in system-level components, particularly in networking protocols where remote exploitation capabilities can be leveraged without user interaction.