CVE-2016-6783 in Android
Summary
by MITRE
An elevation of privilege vulnerability in the MediaTek 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: N/A. Android ID: A-31350044. References: MT-ALPS02943437.
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Analysis
by VulDB Data Team • 07/20/2020
The vulnerability described in CVE-2016-6783 represents a critical elevation of privilege flaw within MediaTek driver components that forms part of the Android operating system ecosystem. This weakness exists in the kernel-level driver code developed by MediaTek, a prominent semiconductor company that provides chipsets for numerous Android devices worldwide. The vulnerability specifically affects the privilege escalation mechanisms within the driver implementation, creating a pathway for malicious applications to gain unauthorized access to kernel-level execution contexts.
The technical flaw manifests through improper privilege validation and access control mechanisms within the MediaTek driver code. When a local application attempts to interact with the vulnerable driver interface, the system fails to properly verify the privileges of the calling process before executing sensitive operations. This oversight allows an attacker who has already compromised a privileged process to leverage the driver vulnerability as a stepping stone for kernel-level code execution. The flaw operates at the intersection of kernel security boundaries where user-space applications can influence kernel behavior through driver interfaces, making it particularly dangerous as it bypasses standard Android security model protections.
The operational impact of this vulnerability is severe given that it enables local privilege escalation to kernel level execution, which represents the highest possible privilege level within the Android operating system. Once successfully exploited, an attacker gains complete control over the device's kernel, allowing for arbitrary code execution, data exfiltration, system modification, and potential persistence mechanisms. The vulnerability requires an initial compromise of a privileged process, but this prerequisite is often achievable through other means such as application sandbox escapes or existing vulnerabilities in the Android framework. The attack vector typically involves exploiting the driver interface through crafted system calls or memory manipulation techniques that trigger the privilege escalation.
From a cybersecurity perspective, this vulnerability aligns with CWE-276, which describes improper privilege management, and maps to ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation'. The flaw demonstrates how driver-level vulnerabilities can serve as critical attack vectors in mobile environments where device manufacturers implement proprietary components that may lack the same level of security scrutiny as standard Android components. Organizations and device manufacturers should consider this vulnerability as part of their comprehensive security assessment protocols, particularly given that MediaTek chipsets are used across numerous Android device models. The vulnerability highlights the importance of thorough security testing for all kernel-level components, including third-party drivers, and underscores the need for proper privilege validation mechanisms throughout the system architecture.
Mitigation strategies for this vulnerability should include immediate patching of affected MediaTek driver components, implementation of kernel address space layout randomization to complicate exploitation attempts, and enhanced monitoring of driver interface usage patterns. System administrators should also consider implementing application control measures and privilege separation policies to limit the potential impact of successful exploitation. Device manufacturers must ensure comprehensive testing of driver components and maintain updated security patches for all MediaTek chipset implementations. The vulnerability serves as a reminder of the critical importance of kernel-level security in mobile environments where device manufacturers often integrate third-party components that may introduce unforeseen security risks.