CVE-2022-50016
📋 TL;DR
A NULL pointer dereference vulnerability in the Linux kernel's Sound Open Firmware (SOF) subsystem for Intel Cannon Lake (CNL) platforms allows a malicious or buggy firmware to crash the kernel. This affects systems using Intel audio hardware with SOF firmware before the kernel processes the firmware ready message. The vulnerability can lead to denial of service (system crash) but not privilege escalation.
💻 Affected Systems
- Linux kernel with SOF subsystem
📦 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to complete system crash and denial of service, requiring physical or remote console access to reboot.
Likely Case
System crash when using buggy or malicious firmware, requiring reboot to restore functionality.
If Mitigated
No impact if patched kernel prevents processing of premature IPC replies before firmware initialization.
🎯 Exploit Status
Exploitation requires ability to load malicious firmware or trigger specific firmware bug conditions. No known public exploits.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 230f646085d17a008b609eb8fe8befb8811868f0 and acacd9eefd0def5a83244d88e5483b5f38ee7287
Vendor Advisory: https://git.kernel.org/stable/c/230f646085d17a008b609eb8fe8befb8811868f0
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Check with your distribution for security updates. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Disable SOF subsystem
linuxPrevent loading of SOF firmware by blacklisting the module
echo 'blacklist snd-sof-pci' >> /etc/modprobe.d/blacklist-sof.conf
update-initramfs -u
reboot
🧯 If You Can't Patch
- Restrict physical and local access to systems with vulnerable hardware
- Monitor for system crashes and investigate any unexpected reboots
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if SOF modules are loaded: 'uname -r' and 'lsmod | grep sof'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is after fix commits and test audio functionality remains working📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- NULL pointer dereference errors related to SOF or audio subsystems
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "kernel panic") AND ("SOF" OR "snd_sof")