CVE-2025-39814
📋 TL;DR
A NULL pointer dereference vulnerability in the Linux kernel's ice driver allows local users to crash the system by triggering a device reset when RDMA support is not loaded. This affects systems using Intel Ethernet Controller E800 Series network adapters with the ice driver. The vulnerability requires local access to trigger the crash.
💻 Affected Systems
- Linux kernel with ice driver for Intel Ethernet Controller E800 Series
📦 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
Kernel panic leading to system crash and denial of service, requiring physical or remote console access to reboot.
Likely Case
Local denial of service through system crash when a user with appropriate permissions triggers a device reset on affected hardware.
If Mitigated
Minimal impact if users lack permissions to write to device reset sysfs files or if RDMA support is enabled.
🎯 Exploit Status
Requires local access and permissions to write to /sys/class/net/<if>/device/reset. Exploitation is straightforward once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commits 60dfe2434eed13082f26eb7409665dfafb38fa51 and/or db783756a7d7cfaea039411971d0dc0a374e85cb
Vendor Advisory: https://git.kernel.org/stable/c/60dfe2434eed13082f26eb7409665dfafb38fa51
Restart Required: No
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For distributions: apply kernel security updates from your vendor. 3. Rebuild and reload ice driver module if using custom kernel.
🔧 Temporary Workarounds
Restrict sysfs reset access
allPrevent non-privileged users from triggering device resets by restricting permissions on the reset sysfs file.
chmod 600 /sys/class/net/*/device/reset
chown root:root /sys/class/net/*/device/reset
Load RDMA support
allEnable RDMA support to avoid the NULL pointer condition that triggers the vulnerability.
modprobe rdma_cm
modprobe ib_core
echo 'rdma_cm' >> /etc/modules-load.d/rdma.conf
echo 'ib_core' >> /etc/modules-load.d/rdma.conf
🧯 If You Can't Patch
- Restrict access to /sys/class/net/*/device/reset to root only using chmod 600 and proper ownership.
- Ensure RDMA modules are loaded at boot to avoid the vulnerable code path.
🔍 How to Verify
Check if Vulnerable:
Check if system has Intel E800 series NICs: lspci | grep -i 'E800' && lsmod | grep ice. Check kernel version: uname -r. Check if RDMA is loaded: lsmod | grep -E 'rdma_cm|ib_core'.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits: git log --oneline | grep -E '60dfe2434eed|db783756a7d7'. Test reset functionality: echo 1 > /sys/class/net/<if>/device/reset (as root, with caution).📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs with 'BUG: kernel NULL pointer dereference' in ice_unplug_aux_dev
- System crash/reboot events following device reset operations
- dmesg output showing ice driver crash during reset
Network Indicators:
- Network interface disappearance following reset attempt
SIEM Query:
event_source="kernel" AND (message:"NULL pointer dereference" AND message:"ice_unplug_aux_dev") OR (message:"BUG:" AND process:"ice")