CVE-2022-50064
📋 TL;DR
This CVE describes a use-after-free vulnerability in the Linux kernel's virtio-blk driver that occurs during system suspend/resume cycles. When a virtual machine with virtio-blk storage resumes from suspend, the kernel may crash due to accessing freed memory, potentially leading to denial of service. This affects Linux systems using virtio-blk drivers for virtualized storage.
💻 Affected Systems
- Linux kernel
📦 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 and system crash leading to complete denial of service, potentially causing data corruption or loss in virtualized environments.
Likely Case
System crash during resume from suspend, requiring reboot and causing temporary service disruption.
If Mitigated
No impact if patched or if suspend/resume functionality is disabled.
🎯 Exploit Status
Exploitation requires ability to trigger suspend/resume cycles, typically requiring local access and appropriate privileges.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel branches via commits 2b54e14535bc34bf649372060d518ec9f2b893b3 and 8d12ec10292877751ee4463b11a63bd850bc09b5
Vendor Advisory: https://git.kernel.org/stable/c/2b54e14535bc34bf649372060d518ec9f2b893b3
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Check with your distribution vendor for specific patched kernel versions. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Disable suspend/resume functionality
linuxPrevent system suspend/resume cycles that trigger the vulnerability
systemctl mask sleep.target suspend.target hibernate.target hybrid-sleep.target
Avoid virtio-blk usage
linuxUse alternative storage drivers in virtualized environments
🧯 If You Can't Patch
- Disable system suspend functionality to prevent trigger conditions
- Monitor for kernel panic logs and have recovery procedures ready
🔍 How to Verify
Check if Vulnerable:
Check kernel version and verify if virtio-blk module is loaded: lsmod | grep virtio_blkCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes the fix commits or check with distribution vendor for patched kernel versions📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages during resume from suspend
- Call traces mentioning virtqueue_add_split or virtblk_add_req in kernel logs
Network Indicators:
- Sudden loss of connectivity from affected VM
SIEM Query:
source="kernel" AND ("virtqueue_add_split" OR "virtblk_add_req" OR "use-after-free")