CVE-2025-37918

/// Technical description

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

Bluetooth: btusb: avoid NULL pointer dereference in skb_dequeue()

A NULL pointer dereference can occur in skb_dequeue() when processing a

QCA firmware crash dump on WCN7851 (0489:e0f3).

[ 93.672166] Bluetooth: hci0: ACL memdump size(589824)

[ 93.672475] BUG: kernel NULL pointer dereference, address: 0000000000000008

[ 93.672517] Workqueue: hci0 hci_devcd_rx [bluetooth]

[ 93.672598] RIP: 0010:skb_dequeue+0x50/0x80

The issue stems from handle_dump_pkt_qca() returning 0 even when a dump

packet is successfully processed. This is because it incorrectly

forwards the return value of hci_devcd_init() (which returns 0 on

success). As a result, the caller (btusb_recv_acl_qca() or

btusb_recv_evt_qca()) assumes the packet was not handled and passes it

to hci_recv_frame(), leading to premature kfree() of the skb.

Later, hci_devcd_rx() attempts to dequeue the same skb from the dump

queue, resulting in a NULL pointer dereferenc

/// 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