CVE-2026-68189

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: hci_sync: Protect UUID list traversal

The hci_sync conversion moved class-of-device and EIR generation from an

HCI request built under hdev->lock to asynchronous command sync work.

The worker holds hdev->req_lock, but that lock does not serialize access

to hdev->uuids against add_uuid() and remove_uuid(), which update the

list under hdev->lock.

The following interleaving can therefore occur:

CPU0 (command sync work) CPU1 (management socket)

fetch uuid from the list

list_del(&uuid->list)

kfree(uuid)

read uuid->size

KASAN reports the resulting use-after-free:

BUG: KASAN: slab-use-after-free in eir_create+0xb8f/0xee0

Read of size 1 at addr ffff88810dbd8620 by task kworker/u17:0/87

Workqueue: hci0 hci_cmd_sync_work

Call Trace:

eir_create+0xb8f/0xee0

hci_update_eir_sync+0x1c0/0x330

hci_cmd_sync_work+0x13c/0x290

p

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References