CVE-2019-9425 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 denial of service with no additional execution privileges needed. User interaction is not needed for exploitation. Product: AndroidVersions: Android-10Android ID: A-110846194
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Analysis
by VulDB Data Team • 09/13/2020
The vulnerability identified as CVE-2019-9425 represents a critical out-of-bounds read flaw within the Bluetooth implementation of Android 10 operating systems. This issue stems from a fundamental missing bounds check in the Bluetooth stack processing logic, where the system fails to properly validate input data before accessing memory locations. The flaw exists within the core Bluetooth protocol handling mechanisms that process incoming wireless packets and connection requests, creating a scenario where malicious actors can craft specially formatted Bluetooth traffic to trigger the vulnerability.
The technical nature of this vulnerability places it squarely within the CWE-129 category of Improper Validation of Array Index, specifically manifesting as an out-of-bounds memory access error. This type of flaw typically occurs when software does not properly validate the range or limits of array indices or buffer offsets before accessing memory locations, allowing attackers to read data beyond the intended boundaries. The vulnerability's classification aligns with ATT&CK technique T1059.005 which covers Command and Scripting Interpreter: Visual Basic, though in this case the exploitation occurs at the kernel level through Bluetooth protocol processing rather than script execution.
The operational impact of CVE-2019-9425 is significant as it enables remote denial of service attacks without requiring any form of user interaction or additional privileges. This means that an attacker positioned within Bluetooth range of a vulnerable Android 10 device can exploit the vulnerability simply by transmitting malformed Bluetooth packets, causing the device's Bluetooth subsystem to crash or become unresponsive. The attack vector is particularly concerning because Bluetooth communication occurs wirelessly and continuously, making it difficult for users to avoid exposure. The vulnerability affects all Android 10 devices regardless of manufacturer, creating a widespread risk across the mobile ecosystem.
Mitigation strategies for this vulnerability should focus on immediate patch deployment through official Android security updates, as Google released fixes for this issue in their security bulletins. Organizations should implement Bluetooth communication monitoring to detect anomalous packet patterns that might indicate exploitation attempts, though this detection method is not foolproof given the nature of the vulnerability. Network administrators should consider implementing Bluetooth access controls and disabling unnecessary Bluetooth services when not actively required. The vulnerability demonstrates the importance of robust input validation in wireless protocol implementations and highlights the need for comprehensive security testing of core system components that handle network communications. Additionally, users should maintain their devices with the latest security patches and avoid connecting to untrusted Bluetooth devices to minimize exposure risk.