CVE-2017-0444 in Android
Summary
by MITRE
An elevation of privilege vulnerability in the Realtek sound driver could enable a local malicious application to execute arbitrary code within the context of the kernel. This issue is rated as High because it first requires compromising a privileged process. Product: Android. Versions: Kernel-3.10. Android ID: A-32705232.
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Analysis
by VulDB Data Team • 11/12/2022
The CVE-2017-0444 vulnerability represents a critical elevation of privilege flaw within the Realtek sound driver component of Android systems running kernel version 3.10. This vulnerability resides in the audio subsystem and specifically affects the kernel-mode driver responsible for handling audio processing tasks. The flaw allows a local malicious application to escalate its privileges and execute arbitrary code within the kernel context, effectively bypassing the standard security boundaries that protect the operating system from unauthorized access. The vulnerability's classification as High severity stems from the requirement of first compromising a privileged process, which significantly reduces the attack surface but does not eliminate the serious implications of successful exploitation. The Android ID A-32705232 identifies this issue within Google's internal tracking system, highlighting its significance in the Android security ecosystem.
The technical root cause of this vulnerability lies in improper input validation and memory management within the Realtek audio driver implementation. When a malicious application attempts to interact with the audio subsystem through specific API calls or malformed data structures, the driver fails to properly validate the incoming parameters before processing them in kernel space. This lack of proper sanitization creates a condition where controlled input can manipulate the driver's execution flow, potentially leading to arbitrary code execution. The vulnerability typically manifests through buffer overflows, use-after-free conditions, or improper privilege checks within the driver's kernel code. According to CWE classification, this vulnerability maps to CWE-119 which encompasses weaknesses related to the use of uncontrolled data in a resource allocation or resource access context, and potentially CWE-787 which deals with out-of-bounds write operations. The exploitation requires an attacker to first establish a foothold within a privileged process context, making this a sophisticated attack vector that aligns with ATT&CK technique T1068 which describes privilege escalation through legitimate system tools and processes.
The operational impact of CVE-2017-0444 extends beyond simple privilege escalation, as successful exploitation can lead to complete system compromise and persistent backdoor access. Once a malicious application gains kernel-level privileges through this vulnerability, it can manipulate system memory, modify critical operating system components, disable security features, and establish persistent access mechanisms. The audio driver's kernel context execution provides attackers with direct access to system resources that are normally protected from user-space applications, including the ability to read and write to any memory location, modify system call tables, and potentially access other connected hardware components. This vulnerability affects all Android devices running kernel 3.10 and the affected Realtek audio driver implementations, making it a widespread concern across numerous device models and manufacturers. The local nature of the attack means that exploitation requires physical access or prior compromise of a legitimate application, but the consequences are severe enough to warrant immediate attention from security teams and device manufacturers.
Mitigation strategies for CVE-2017-0444 focus on both immediate patching and defensive measures. Device manufacturers and Android developers should prioritize applying the relevant security patches that address the driver implementation flaws and correct the improper input validation mechanisms. The most effective immediate solution involves updating the Realtek audio driver to a version that properly validates all input parameters and implements robust memory management practices. Organizations should also implement application whitelisting and monitoring of audio subsystem access patterns to detect potential exploitation attempts. System administrators should consider disabling unnecessary audio functionality when not required, particularly in enterprise environments where the attack surface needs to be minimized. From a defensive perspective, implementing kernel address space layout randomization and other exploit mitigation techniques can make successful exploitation more difficult. The vulnerability highlights the importance of comprehensive driver security testing and the need for regular security audits of kernel components, particularly those handling user input or providing access to critical system resources. Additionally, maintaining up-to-date security patches and implementing proper security monitoring can help detect and prevent exploitation attempts before they can cause significant damage to the affected systems.