CVE-2016-8435 in Android
Summary
by MITRE
An elevation of privilege vulnerability in the NVIDIA GPU driver could enable a local malicious application to execute arbitrary code within the context of the kernel. This issue is rated as Critical due to the possibility of a local permanent device compromise, which may require reflashing the operating system to repair the device. Product: Android. Versions: Kernel-3.18. Android ID: A-32700935. References: N-CVE-2016-8435.
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Analysis
by VulDB Data Team • 10/27/2022
This critical elevation of privilege vulnerability exists within the NVIDIA GPU driver component of Android systems running kernel version 3.18. The flaw allows a local malicious application to escalate its privileges and execute arbitrary code with kernel-level permissions, effectively bypassing the operating system's security boundaries. The vulnerability represents a severe compromise of the system's integrity since it enables an attacker with local access to gain root-level control over the device's graphics processing unit and underlying kernel operations. The Android ID A-32700935 identifies this specific issue within the Android security framework, highlighting its significance in mobile device security. This type of vulnerability falls under CWE-269, which addresses privilege escalation issues in operating systems and network services, specifically targeting the improper handling of kernel-level access controls.
The technical exploitation of this vulnerability occurs through a flaw in the GPU driver's privilege management mechanisms, allowing a malicious application to manipulate kernel memory or execution paths. When an application attempts to interact with the GPU driver, it can potentially trigger a code execution path that lacks proper input validation or privilege checks. The attack vector requires local system access, meaning the malicious application must already be running on the device, but once successful, it provides complete control over the kernel execution environment. The exploitation process typically involves leveraging buffer overflows, improper access control, or race conditions within the driver's implementation that permit unauthorized privilege escalation. This vulnerability directly impacts the Android security model by undermining the isolation between user-space applications and kernel-space operations, creating a persistent backdoor that could be used for further system compromise.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it creates a permanent compromise of the device that may require complete system reinstallation or reflashing to remediate properly. Once exploited, the malicious code can maintain persistence within the kernel, making it extremely difficult to detect and remove without complete system recovery. The compromised device becomes vulnerable to additional attacks, data theft, and potential use as a pivot point for attacking other connected systems. This vulnerability is particularly concerning for mobile devices since they often contain sensitive personal and corporate data, and the kernel-level compromise provides attackers with access to all system resources, including encryption keys, user credentials, and protected data storage. The severity classification as Critical reflects the potential for complete device takeover and the difficulty of complete remediation without system-level intervention.
Mitigation strategies for this vulnerability involve immediate patching of the NVIDIA GPU driver components within Android systems, ensuring that all devices running kernel 3.18 receive the appropriate security updates from manufacturers. System administrators and device manufacturers should prioritize the deployment of these patches across all affected devices, particularly those in enterprise environments where device compromise could lead to significant data breaches. The implementation of additional security measures such as kernel address space layout randomization kASLR and stack canaries can help reduce the effectiveness of exploitation attempts. Organizations should also consider implementing runtime monitoring solutions to detect suspicious kernel-level activity that might indicate exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and persistence mechanisms, requiring security teams to monitor for unusual kernel module loading or memory manipulation activities. Regular security audits and vulnerability assessments should be conducted to identify and remediate similar issues in other device drivers and system components.