CVE-2023-53828 Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_add_adv_monitor()
A use-after-free vulnerability in the Linux kernel Bluetooth subsystem allows attackers to cause a denial of service or potentially execute code.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53828?
CVE-2023-53828 is a high-severity use after free vulnerability in Linux, published on 9 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_add_adv_monitor()
KSAN reports use-after-free in hci_add_adv_monitor().
While adding an adv monitor, hci_add_adv_monitor() calls -> msft_add_monitor_pattern() calls -> msft_add_monitor_sync() calls -> msft_le_monitor_advertisement_cb() calls in an error case -> hci_free_adv_monitor() which frees the *moniter.
This is referenced by bt_dev_dbg() in hci_add_adv_monitor().
Fix the bt_dev_dbg() by using handle instead of monitor->handle.
Which versions are affected by CVE-2023-53828?
How do I fix CVE-2023-53828?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2023-53828 being exploited?
There is no known exploitation of CVE-2023-53828 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53828, DEBIAN-CVE-2023-53828, GHSA-jx2x-x589-6cw3, UBUNTU-CVE-2023-53828.