CVE-2021-34401
📋 TL;DR
This vulnerability in NVIDIA's Linux kernel driver allows improper access control in the nvmap NVGPU_IOCTL_CHANNEL_SET_ERROR_NOTIFIER interface. Attackers could potentially execute arbitrary code, compromise system integrity, or cause denial of service. It affects systems running NVIDIA GPU drivers on Linux distributions.
💻 Affected Systems
- NVIDIA GPU Display Driver for Linux
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise through kernel-level code execution leading to complete control of affected systems
Likely Case
Local privilege escalation allowing attackers to gain root access on vulnerable systems
If Mitigated
Limited impact with proper access controls and isolation preventing unauthorized users from accessing GPU interfaces
🎯 Exploit Status
Requires local access to the system and knowledge of the vulnerable interface
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 470.42.01 and later
Vendor Advisory: https://nvidia.custhelp.com/app/answers/detail/a_id/5259
Restart Required: Yes
Instructions:
1. Download NVIDIA driver version 470.42.01 or later from NVIDIA's website. 2. Stop all graphical sessions. 3. Run the installer with appropriate permissions. 4. Reboot the system.
🔧 Temporary Workarounds
Restrict GPU device access
linuxLimit access to GPU device files to prevent unauthorized users from exploiting the vulnerability
chmod 600 /dev/nvidia*
chown root:root /dev/nvidia*
🧯 If You Can't Patch
- Implement strict access controls to limit which users can access GPU interfaces
- Isolate systems with vulnerable drivers from untrusted users and networks
🔍 How to Verify
Check if Vulnerable:
Check NVIDIA driver version with 'nvidia-smi' or 'cat /proc/driver/nvidia/version'Check Version:
nvidia-smi --query-gpu=driver_version --format=csv,noheaderVerify Fix Applied:
Verify driver version is 470.42.01 or later using 'nvidia-smi' command📡 Detection & Monitoring
Log Indicators:
- Unusual access patterns to /dev/nvidia* device files
- Failed privilege escalation attempts
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
source="kernel" AND (device="nvidia" OR process="nvidia") AND action="access_denied"