CVE-2026-90254: Linux

EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: free the advertising instance on the failure and cancel paths adv_timeout_expire() hands a kmalloc()ed instance byte to hci_cmd_sync_queue() with a NULL destroy callback, and only adv_timeout_expire_sync() frees it. That leaks on two paths: - the return value is not checked, and hci_cmd_sync_queue() does not take ownership when it fails (-ENETDOWN, -ENODEV, -ENOMEM); - a cancelled entry is not released, as _hci_cmd_sync_cancel_entry() does not free entry->data when there is no destroy callback. hci_cmd_sync_clear() cancels every pending entry when the controller is unregistered. Free the buffer from a destroy callback, and in the caller when the entry could not be queued at all.

Affected products

• Linux Linux: from 6.1, before 6.1.188 (fixed in 6.1.188); from 6.2, before 6.6.157 (fixed in 6.6.157); from 6.7, before 6.12.110 (fixed in 6.12.110); from 6.13, before 6.18.52 (fixed in 6.18.52); from 6.19, before 7.2.6 (fixed in 7.2.6)

Published 2026-09-17. Last modified 2026-09-17.