CVE-2016-8394 in Android
Summary
by MITRE
An elevation of privilege vulnerability in the Synaptics touchscreen 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-31913197.
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Analysis
by VulDB Data Team • 07/20/2020
The vulnerability identified as CVE-2016-8394 represents a critical elevation of privilege flaw within the Synaptics touchscreen driver component of Android systems running kernel version 3.10. This security weakness resides in the kernel-level driver responsible for handling touchscreen input operations and allows a local malicious application to escalate its privileges and execute arbitrary code with kernel-level permissions. The vulnerability is classified as High severity due to its requirement for initial compromise of a privileged process, which significantly increases the attack surface and potential impact on system integrity.
This flaw stems from improper input validation and memory management within the Synaptics touchscreen driver implementation, creating a path for privilege escalation attacks. The vulnerability specifically affects the interaction between the touchscreen driver and the Android kernel, where insufficient bounds checking or improper handling of user-supplied data allows an attacker to manipulate kernel memory structures. The issue manifests when a malicious application attempts to exploit a weakness in how the driver processes touchscreen input events, potentially leading to arbitrary code execution in kernel space. This type of vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which covers heap-based buffer overflow conditions, both of which are common in kernel driver implementations.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it provides attackers with complete control over the affected Android device. Once exploited, the malicious application can bypass Android's security model and gain unrestricted access to system resources, potentially enabling data theft, persistent backdoor installation, or complete system compromise. The attack requires the initial compromise of a privileged process, which may be achieved through various means including social engineering, phishing attacks, or exploitation of other vulnerabilities in the Android ecosystem. This attack pattern aligns with ATT&CK technique T1068, which covers "Exploitation for Privilege Escalation," and T1059, which covers "Command and Scripting Interpreter," as the compromised application can leverage the elevated privileges to execute additional malicious code.
Mitigation strategies for CVE-2016-8394 involve immediate patching of affected Android systems through security updates from device manufacturers, as well as implementing runtime protections such as kernel address space layout randomization and stack canaries. System administrators should also consider implementing application control measures to prevent unauthorized applications from running with elevated privileges and monitor for suspicious activity related to touchscreen driver interactions. The vulnerability demonstrates the critical importance of secure driver development practices and proper input validation in kernel space, as highlighted by the Common Weakness Enumeration standards and the need for comprehensive security testing of device drivers. Organizations should also implement robust monitoring solutions to detect potential exploitation attempts and maintain up-to-date threat intelligence on similar vulnerabilities in touchscreen and input device drivers.