CVE-2025-39906
📋 TL;DR
A null pointer dereference vulnerability in the AMD display driver for Linux kernels allows local attackers to cause a kernel panic or system crash by accessing an invalid I2C adapter after GPU unbinding. This affects Linux systems with AMD graphics hardware using the affected driver. The vulnerability requires local access to the system.
💻 Affected Systems
- Linux kernel with AMD display driver (drm/amd/display)
📦 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 →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
Kernel panic leading to system crash and denial of service, potentially causing data loss or service disruption.
Likely Case
System crash or instability when applications attempt to access the GPU after driver unbinding, requiring reboot.
If Mitigated
Minimal impact with proper access controls preventing local users from triggering the condition.
🎯 Exploit Status
Requires local access and ability to trigger GPU unbinding or access the I2C adapter after unbinding.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commit 89923fb7ead4fdd37b78dd49962d9bb5892403e6 or backports
Vendor Advisory: https://git.kernel.org/stable/c/1dfd2864a1c4909147663e5a27c055f50f7c2796
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. For distributions: Use package manager (apt/yum/dnf) to update kernel. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Prevent GPU unbinding
linuxRestrict users from unbinding GPU drivers to prevent triggering the vulnerability
echo 'blacklist amdgpu' >> /etc/modprobe.d/blacklist.conf
update-initramfs -u
🧯 If You Can't Patch
- Restrict local user access to systems with AMD GPUs
- Implement monitoring for kernel panic events related to GPU operations
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if AMD GPU driver is loaded: lsmod | grep amdgpu && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and contains the fix commit: git log --oneline | grep 89923fb7ead4📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Null pointer dereference errors in dmesg
- GPU driver crash logs
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("null pointer" OR "kernel panic" OR "oops") AND "amdgpu"