CVE-2022-48844
📋 TL;DR
This CVE describes a use-after-free vulnerability in the Linux kernel's Bluetooth subsystem where the sent_cmd memory buffer is not properly freed before freeing the hci_dev structure, causing memory leaks. This affects Linux systems with Bluetooth functionality enabled. Attackers could potentially exploit this to cause denial of service or execute arbitrary code.
💻 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 →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, system crash, or potential arbitrary code execution with kernel privileges leading to complete system compromise.
Likely Case
Memory exhaustion leading to system instability, denial of service, or kernel crashes requiring system reboot.
If Mitigated
Limited impact with proper memory management and isolation controls in place, potentially just minor performance degradation.
🎯 Exploit Status
Exploitation requires local access and knowledge of kernel memory management. No public exploits known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patched in stable kernel commits: 3679ccc09d8806686d579095ed504e045af7f7d6, 9473d06bd1c8da49eafb685aa95a290290c672dd, dd3b1dc3dd050f1f47cd13e300732852414270f8
Vendor Advisory: https://git.kernel.org/stable/c/3679ccc09d8806686d579095ed504e045af7f7d6
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Check your distribution's security advisories for specific patched kernel versions. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Disable Bluetooth
linuxDisable Bluetooth functionality to prevent exploitation of vulnerable code paths
sudo systemctl stop bluetooth
sudo systemctl disable bluetooth
sudo rfkill block bluetooth
🧯 If You Can't Patch
- Disable Bluetooth functionality completely on affected systems
- Implement strict access controls to limit local user access to vulnerable systems
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from your distribution's security advisoriesCheck Version:
uname -rVerify Fix Applied:
Verify kernel version after update matches patched version from vendor advisory📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Out of memory errors
- Bluetooth subsystem crashes in dmesg
Network Indicators:
- Unusual Bluetooth connection attempts
- Bluetooth service instability
SIEM Query:
source="kernel" AND ("panic" OR "Oops" OR "segfault") AND "bluetooth"🔗 References
- https://git.kernel.org/stable/c/3679ccc09d8806686d579095ed504e045af7f7d6
- https://git.kernel.org/stable/c/9473d06bd1c8da49eafb685aa95a290290c672dd
- https://git.kernel.org/stable/c/dd3b1dc3dd050f1f47cd13e300732852414270f8
- https://git.kernel.org/stable/c/3679ccc09d8806686d579095ed504e045af7f7d6
- https://git.kernel.org/stable/c/9473d06bd1c8da49eafb685aa95a290290c672dd
- https://git.kernel.org/stable/c/dd3b1dc3dd050f1f47cd13e300732852414270f8
