CVE-2023-53071
📋 TL;DR
A NULL pointer dereference vulnerability in the MediaTek MT76 Wi-Fi driver for Linux kernels allows local attackers to cause a kernel panic (system crash) when removing a mt7921e PCI card without proper firmware. This affects Linux systems using MediaTek Wi-Fi hardware. The vulnerability requires physical or local access to trigger.
💻 Affected Systems
- Linux kernel with MediaTek MT76 Wi-Fi 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 →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 complete system crash and denial of service, requiring physical reboot.
Likely Case
System crash when removing faulty MediaTek Wi-Fi hardware, causing temporary service disruption.
If Mitigated
No impact if proper access controls prevent local users from removing hardware or if vulnerable driver isn't loaded.
🎯 Exploit Status
Exploitation requires local access and specific hardware conditions (mt7921e card without firmware). Simple trigger via device removal.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 2d34f27714c97a9786a30b3bb54944d6d8ed612f, 41130c32f3a18fcc930316da17f3a5f3bc326aa1, dffe86df26aee01a5fc56a175b7a7f157961e370
Vendor Advisory: https://git.kernel.org/stable/c/2d34f27714c97a9786a30b3bb54944d6d8ed612f
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For distributions: Use package manager (apt/yum/dnf) to install latest kernel updates. 3. Reboot system to load patched kernel.
🔧 Temporary Workarounds
Blacklist MT76 driver
linuxPrevent loading of vulnerable MT76 driver module
echo 'blacklist mt76' | sudo tee /etc/modprobe.d/blacklist-mt76.conf
sudo update-initramfs -u
sudo reboot
Remove MediaTek hardware
allPhysically remove or disable MediaTek mt7921e Wi-Fi cards
🧯 If You Can't Patch
- Restrict physical access to prevent hardware removal by unauthorized users
- Implement strict access controls to prevent local users from removing PCI devices
🔍 How to Verify
Check if Vulnerable:
Check if MT76 driver is loaded: lsmod | grep mt76. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits or is newer than vulnerable versions. Check dmesg for no NULL pointer errors during device removal.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- NULL pointer dereference errors mentioning mt76_unregister_device
Network Indicators:
- Sudden loss of Wi-Fi connectivity followed by system crash
SIEM Query:
source="kernel" AND "NULL pointer dereference" AND "mt76"