CVE-2022-50339
📋 TL;DR
This is a race condition vulnerability in the Linux kernel's Bluetooth subsystem that can cause a kernel panic or system crash. It occurs when multiple processes attempt to initialize and remove Bluetooth management interfaces simultaneously, leading to use of uninitialized work structures. Systems using Bluetooth functionality with affected kernel versions are vulnerable.
💻 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 leading to system crash and denial of service, potentially requiring physical reboot of affected systems.
Likely Case
System instability or crash when Bluetooth operations are performed concurrently by multiple processes or users.
If Mitigated
Minimal impact if Bluetooth functionality is disabled or not in use, or if systems are patched.
🎯 Exploit Status
Exploitation requires triggering a specific race condition during Bluetooth operations. The vulnerability was discovered through syzbot fuzzing.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees. Specific version depends on distribution.
Vendor Advisory: https://git.kernel.org/stable/c/e53c6180db8dd09de94e0a3bdf4fef6f5f9dd6e6
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. For custom kernels, apply commit e53c6180db8dd09de94e0a3bdf4fef6f5f9dd6e6 or f74ca25d6d6629ffd4fd80a1a73037253b57d06b. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable Bluetooth
linuxDisable Bluetooth functionality to prevent the race condition from being triggered.
sudo systemctl stop bluetooth
sudo systemctl disable bluetooth
sudo rfkill block bluetooth
🧯 If You Can't Patch
- Disable Bluetooth functionality completely using system controls
- Restrict Bluetooth access to trusted users only and monitor for abnormal Bluetooth operations
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with distribution's security advisories. Vulnerable if using unpatched kernel with Bluetooth enabled.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to patched version and check that Bluetooth functionality works without crashes during concurrent operations.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages related to Bluetooth
- System crash logs mentioning mgmt_index_removed or hci_dev functions
- Bluetooth subsystem errors in dmesg
Network Indicators:
- Abnormal Bluetooth connection patterns that could trigger race conditions
SIEM Query:
source="kernel" AND ("panic" OR "oops") AND ("bluetooth" OR "hci" OR "mgmt")