CVE-2022-50115
📋 TL;DR
This CVE describes a double-free memory corruption vulnerability in the Linux kernel's Sound Open Firmware (SOF) subsystem. When byte control sanity checks fail during audio topology loading, the system frees memory but doesn't null the pointer, allowing subsequent rollback code to free it again. This affects systems using SOF audio drivers with vulnerable kernel versions.
💻 Affected Systems
- Linux kernel with SOF (Sound Open Firmware) 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 →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, potential privilege escalation if attacker can control memory layout, or arbitrary code execution in kernel context.
Likely Case
System instability, crashes, or denial of service when processing malformed audio topology data.
If Mitigated
No impact if patched or if SOF audio subsystem is not in use.
🎯 Exploit Status
Exploitation requires triggering specific error conditions in audio topology loading, making reliable exploitation challenging.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 8463986b54295e6b65ddf2b7c65627d01ce7643b, c2eddfcafcffaf1b9245ea0dde9143bbfb47d5d1, or d5bd47f3ca124058a8e87eae4508afeda2132611
Vendor Advisory: https://git.kernel.org/stable/c/8463986b54295e6b65ddf2b7c65627d01ce7643b
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution. 2. For custom kernels, apply the fix commits. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Disable SOF audio subsystem
linuxPrevents the vulnerable code from being loaded by disabling the SOF audio driver.
echo 'blacklist snd-sof-pci' > /etc/modprobe.d/disable-sof.conf
update-initramfs -u
reboot
🧯 If You Can't Patch
- Restrict local user access to systems with vulnerable kernels
- Monitor system logs for kernel panics or audio subsystem errors
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if SOF modules are loaded: uname -r && lsmod | grep -i sofCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is after fix commits and test audio functionality remains working📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- Audio subsystem errors in dmesg
- System crashes during audio operations
Network Indicators:
- None - local vulnerability only
SIEM Query:
search 'kernel: BUG:' OR 'kernel: general protection fault' OR 'sof' in system logs