CVE-2018-3979 in Display Driver
Summary
by MITRE
A remote denial-of-service vulnerability exists in the way the Nouveau Display Driver (the default Ubuntu Nvidia display driver) handles GPU shader execution. A specially crafted pixel shader can cause remote denial-of-service issues. An attacker can provide a specially crafted website to trigger this vulnerability. This vulnerability can be triggered remotely after the user visits a malformed website. No further user interaction is required. Vulnerable versions include Ubuntu 18.04 LTS (linux 4.15.0-29-generic x86_64), Nouveau Display Driver NV117 (vermagic: 4.15.0-29-generic SMP mod_unload).
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/21/2023
The vulnerability described in CVE-2018-3979 represents a critical remote denial-of-service issue within the Nouveau display driver ecosystem, which serves as the open-source graphics driver for nvidia hardware in Ubuntu systems. This flaw specifically targets the GPU shader execution handling mechanism within the NV117 driver component, which is part of the broader nouveau driver suite that provides graphics support for nvidia graphics cards in linux environments. The vulnerability manifests when the driver processes specially crafted pixel shaders that are designed to exploit memory management and execution flow within the graphics processing unit's shader units.
The technical exploitation of this vulnerability occurs through the manipulation of shader code that is executed during graphics rendering operations. When a user visits a malicious website containing crafted pixel shader code, the Nouveau driver attempts to process this shader data without proper validation or sanitization of the input. This processing leads to a condition where the GPU's execution environment becomes unstable, causing the graphics subsystem to crash or become unresponsive. The vulnerability specifically affects the way the driver handles shader compilation and execution, creating a path where malformed shader data can trigger a system-wide denial-of-service condition that impacts the entire graphical interface and potentially the underlying operating system's stability.
The operational impact of this vulnerability extends beyond simple system crashes, as it represents a significant security risk for users who browse the internet regularly. The vulnerability's remote trigger capability means that users do not need to download or execute any malicious files directly; simply visiting a compromised website is sufficient to trigger the exploit. This characteristic makes the vulnerability particularly dangerous in environments where users have limited control over their browsing environment or where automated browser interactions occur. The affected Ubuntu 18.04 LTS system with kernel version 4.15.0-29-generic demonstrates how widely deployed systems can be impacted by such low-level driver vulnerabilities that affect fundamental system operations rather than just application-level security.
From a cybersecurity perspective, this vulnerability aligns with several ATT&CK framework techniques including T1203 (Exploitation for Execution) and T1059 (Command and Scripting Interpreter) as it leverages graphics processing unit capabilities to achieve system-level disruption. The vulnerability also relates to CWE-125 (Out-of-bounds Read) and CWE-787 (Out-of-bounds Write) categories, as the improper handling of shader data can lead to memory corruption within the driver's execution environment. The fact that this vulnerability affects the default Ubuntu display driver highlights the importance of considering device drivers as critical system components that require regular security updates and monitoring, as they often operate with elevated privileges and direct hardware access that can be exploited to compromise system integrity.
Mitigation strategies for this vulnerability should include immediate system updates to patch the Nouveau driver components, as well as implementing network-level controls to prevent access to known malicious websites. System administrators should also consider disabling or restricting GPU shader execution in environments where such vulnerabilities are exploited, and implementing monitoring solutions that can detect unusual GPU memory usage patterns or driver crashes that may indicate exploitation attempts. The vulnerability underscores the necessity of maintaining comprehensive patch management programs for all system components, including graphics drivers, as these components often serve as attack vectors for sophisticated adversaries seeking to gain persistent access to systems.