CVE-2023-53828

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.

This vulnerability is rated as Moderate impact because exploitation requires local access with administrative privileges (such as CAP_NET_ADMIN) to register Bluetooth advertisement monitors. In typical Red Hat Enterprise Linux server deployments, Bluetooth hardware is absent or disabled by default, which drastically restricts the attack surface. Furthermore, the issue is triggered only under an error condition during advertisement monitor setup, limiting the practical impact to a localized denial of service rather than arbitrary code execution.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.