CVE-2023-51779
📋 TL;DR
This vulnerability in the Linux kernel's Bluetooth subsystem allows a local attacker to trigger a use-after-free condition through a race condition in bt_sock_ioctl. This can potentially lead to privilege escalation or system crashes. Any Linux system with Bluetooth enabled and running kernel versions up to 6.6.8 is affected.
💻 Affected Systems
- Linux kernel
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation to root, allowing complete system compromise and potential persistence mechanisms.
Likely Case
Kernel panic or system crash leading to denial of service, with potential for limited privilege escalation in specific configurations.
If Mitigated
Minimal impact if Bluetooth is disabled or proper access controls restrict local user privileges.
🎯 Exploit Status
Requires local access and race condition triggering, making exploitation somewhat complex but feasible for skilled attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel 6.6.9 and later, or distributions with backported fixes
Vendor Advisory: https://github.com/torvalds/linux/commit/2e07e8348ea454615e268222ae3fc240421be768
Restart Required: Yes
Instructions:
1. Update kernel to version 6.6.9 or later. 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
linuxUse kernel capabilities or SELinux/AppArmor to restrict access to Bluetooth sockets
sudo setcap -r /usr/bin/bluetoothctl
sudo chmod 750 /var/run/bluetooth
🧯 If You Can't Patch
- Disable Bluetooth subsystem completely if not required
- Implement strict access controls to limit which users can access Bluetooth functionality
🔍 How to Verify
Check if Vulnerable:
Check kernel version: uname -r. If version is 6.6.8 or earlier, system is vulnerable if Bluetooth is enabled.Check Version:
uname -rVerify Fix Applied:
After patching, verify kernel version is 6.6.9 or later with uname -r, and check that Bluetooth still functions if needed.📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages in /var/log/kern.log or dmesg
- Bluetooth subsystem crashes
- Unexpected privilege escalation attempts
Network Indicators:
- None - local exploit only
SIEM Query:
source="kernel" AND ("oops" OR "use-after-free" OR "bt_sock")