CVE-2016-8818 in GPU Driver
Summary
by MITRE
All versions of NVIDIA Windows GPU Display contain a vulnerability in the kernel mode layer (nvlddmkm.sys) handler for DxgDdiEscape where a pointer passed from a user to the driver is used without validation, leading to denial of service or potential escalation of privileges.
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Analysis
by VulDB Data Team • 07/09/2019
The vulnerability identified as CVE-2016-8818 resides within NVIDIA's Windows GPU display drivers, specifically targeting the kernel mode layer component known as nvlddmkm.sys. This flaw manifests in the DxgDdiEscape handler which processes escape commands sent from user-mode applications to the graphics driver. The core issue stems from insufficient validation of pointers received from user space, creating a dangerous condition where unvalidated memory references can be dereferenced within the privileged kernel context. Such pointer validation failures represent a classic security weakness that can be exploited to compromise system integrity.
The technical nature of this vulnerability aligns with CWE-787, which describes out-of-bounds writes and reads, and CWE-125, which covers out-of-bounds read conditions. The flaw occurs when user-mode applications pass pointers to the kernel-mode driver through the DxgDdiEscape interface without proper verification of their validity or bounds. When the kernel mode component processes these unvalidated pointers, it can lead to unpredictable behavior including system crashes, denial of service conditions, or potentially more severe privilege escalation attacks. The attack surface is particularly concerning because graphics drivers operate with high privileges and have extensive access to system resources and memory.
From an operational impact perspective, this vulnerability presents a significant risk to system stability and security. The denial of service aspect can result in complete system crashes or GPU driver failures, rendering graphics functionality unavailable and potentially causing system instability. More critically, the potential for privilege escalation means that malicious actors could leverage this flaw to elevate their privileges from standard user level to kernel level access. This would enable them to bypass operating system security controls, access protected memory regions, and potentially execute arbitrary code with the highest system privileges. The vulnerability affects all versions of NVIDIA Windows GPU display drivers, making it a widespread concern across multiple product lines.
Mitigation strategies for CVE-2016-8818 should focus on immediate patch deployment from NVIDIA, which addresses the pointer validation issue in the kernel mode driver component. System administrators should prioritize updating to the latest NVIDIA driver versions that contain the necessary fixes. Additionally, implementing monitoring for suspicious DxgDdiEscape API usage patterns can help detect potential exploitation attempts. Network segmentation and privilege separation measures can limit the potential impact if exploitation occurs. The vulnerability also highlights the importance of kernel-mode code security practices and proper input validation, aligning with ATT&CK technique T1068 which covers privilege escalation through kernel exploits. Organizations should also consider implementing exploit prevention mechanisms and maintaining up-to-date security patches across all GPU driver components to prevent similar vulnerabilities from being exploited.