CVE-2023-53252
📋 TL;DR
This is a use-after-free vulnerability in the Linux kernel's Bluetooth subsystem that allows local attackers to cause memory corruption, potentially leading to system crashes or arbitrary code execution. It affects Linux systems with Bluetooth enabled, particularly when using BlueZ or performing Bluetooth Low Energy operations. The vulnerability occurs when lists of pending Bluetooth connections are modified while being iterated without proper synchronization.
💻 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 →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
Local privilege escalation to kernel-level code execution, complete system compromise, or persistent denial of service.
Likely Case
System crash (kernel panic) or instability when Bluetooth operations are performed, potentially requiring system reboot.
If Mitigated
Limited to denial of service in controlled environments with restricted Bluetooth access and proper kernel hardening.
🎯 Exploit Status
Requires local access or Bluetooth proximity. Triggering requires specific Bluetooth operations that cause list modifications during iteration. The KASAN report shows it can be triggered by BlueZ mgmt-tester or iso-tester cases.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 13ad45ad14df992a6754a130a19abc8c142d54e2, 195ef75e19287b4bc413da3e3e3722b030ac881e, cef88a0fd8e9c2e838162fbb742b3e713b811a7e
Vendor Advisory: https://git.kernel.org/stable/c/13ad45ad14df992a6754a130a19abc8c142d54e2
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For distributions: Use package manager (apt/yum/dnf) to update kernel package. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable Bluetooth
linuxCompletely disable Bluetooth subsystem to prevent exploitation
sudo systemctl stop bluetooth
sudo systemctl disable bluetooth
sudo modprobe -r btusb bluetooth
Restrict Bluetooth access
linuxLimit Bluetooth operations to trusted users only
sudo chmod 600 /var/run/bluetooth/*
sudo setfacl -m u:trusted_user:rw /var/run/bluetooth/*
🧯 If You Can't Patch
- Disable Bluetooth functionality entirely if not required
- Implement strict access controls to limit who can perform Bluetooth operations
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if Bluetooth is active: 'uname -r' and 'systemctl status bluetooth'Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits: 'uname -r' and check distribution's security advisories📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- KASAN reports in dmesg
- Bluetooth subsystem crashes in system logs
Network Indicators:
- Unusual Bluetooth connection patterns
- Multiple failed Bluetooth connection attempts
SIEM Query:
source="kernel" AND ("KASAN" OR "use-after-free" OR "slab-use-after-free") AND "bluetooth"