CVE-2024-46860
📋 TL;DR
This vulnerability in the Linux kernel's MediaTek MT7921 WiFi driver allows a NULL pointer dereference when disabling WiFi while IPv6 address changes are being processed. It affects Linux systems using the mt76 driver for MediaTek MT7921 WiFi chips. The vulnerability can cause kernel crashes or denial of service.
💻 Affected Systems
- Linux kernel with mt76 WiFi 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 system crash and denial of service, requiring physical or remote console access to reboot.
Likely Case
System instability or crash when disabling WiFi with IPv6 enabled, requiring reboot to restore functionality.
If Mitigated
Minor service interruption during WiFi disable operations with proper monitoring and automated recovery.
🎯 Exploit Status
Exploitation requires ability to disable WiFi interface, typically requiring local user or administrative access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel stable releases containing commits 479ffee68d59c599f8aed8fa2dcc8e13e7bd13c3, 4bfee9346d8c17d928ef6da2b8bffab88fa2a553, or 8d92bafd4c67efb692f722d73a07412b5f88c6d6
Vendor Advisory: https://git.kernel.org/stable/c/479ffee68d59c599f8aed8fa2dcc8e13e7bd13c3
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from distribution repositories. 2. Reboot system to load new kernel. 3. Verify driver version and kernel version after reboot.
🔧 Temporary Workarounds
Disable IPv6 on WiFi interfaces
linuxPrevents the IPv6 address change notifier from being called when disabling WiFi
sudo sysctl -w net.ipv6.conf.wlan0.disable_ipv6=1
Avoid disabling WiFi while connected
linuxDisconnect from networks before disabling WiFi interface
sudo nmcli device disconnect wlan0
sudo ip link set wlan0 down
🧯 If You Can't Patch
- Implement monitoring for kernel panics and automated recovery procedures
- Restrict WiFi management operations to trusted administrators only
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if using mt76 driver with MT7921 hardware: lsmod | grep mt76; dmesg | grep mt7921Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and check for absence of NULL pointer errors in kernel logs: dmesg | grep -i 'null pointer'📡 Detection & Monitoring
Log Indicators:
- Kernel NULL pointer dereference messages
- mt7921_ipv6_addr_change errors in dmesg
- Kernel panic logs
Network Indicators:
- Unexpected WiFi interface disconnections
- Network service interruptions
SIEM Query:
source="kernel" AND ("NULL pointer" OR "mt7921" OR "kernel panic")