CVE-2024-40926
📋 TL;DR
A vulnerability in the Linux kernel's Nouveau graphics driver causes a kernel panic when attempting to schedule hotplug detection work on headless graphics cards. This affects Linux systems using Nouveau driver with headless NVIDIA graphics hardware, potentially causing system crashes during power management operations.
💻 Affected Systems
- Linux kernel with Nouveau driver
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
System crash (kernel panic) leading to denial of service, potentially causing data loss or service disruption.
Likely Case
System crash during runtime power management resume operations, requiring manual reboot.
If Mitigated
No impact if system doesn't use Nouveau driver or doesn't have headless NVIDIA graphics hardware.
🎯 Exploit Status
Exploitation requires triggering runtime PM resume on affected hardware, which could occur during normal system operations like suspend/resume cycles.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commits 227349998e5740f14d531b0f0d704e66b1ed3c2f and b96a225377b6602299a03d2ce3c289b68cd41bb7
Vendor Advisory: https://git.kernel.org/stable/c/227349998e5740f14d531b0f0d704e66b1ed3c2f
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Check distribution-specific security advisories. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Disable Nouveau driver
linuxBlacklist Nouveau driver to prevent loading
echo 'blacklist nouveau' >> /etc/modprobe.d/blacklist-nouveau.conf
update-initramfs -u
Use proprietary NVIDIA driver
linuxReplace Nouveau with NVIDIA proprietary driver
apt-get install nvidia-driver-xxx # Debian/Ubuntu
yum install nvidia-driver # RHEL/CentOS
🧯 If You Can't Patch
- Disable runtime power management for affected systems
- Avoid using headless NVIDIA graphics hardware with Nouveau driver
🔍 How to Verify
Check if Vulnerable:
Check if system uses Nouveau driver and has headless NVIDIA hardware: lsmod | grep nouveau && lspci | grep -i nvidiaCheck Version:
uname -rVerify Fix Applied:
Check kernel version includes fix commits: uname -r and verify with distribution security advisories📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- Nouveau driver initialization failures
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("BUG" OR "panic" OR "nouveau" AND "hpd_work")