CVE-2026-98461

/// Technical description

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

Bluetooth: hci_sock: validate event length before filtering

is_filtered_packet() reads the event code from skb->data[0] without first

checking that the skb is nonempty. When an opcode filter is configured,

it also reads the command opcode at offsets 3 or 4 without checking that

a Command Complete or Command Status event is long enough.

hci_send_to_sock() invokes the filter before hci_event_packet() validates

the event header. A malformed event supplied by a controller or a vhci

device can therefore cause an out-of-bounds read.

Keep the unmasked event code for the opcode checks. The masked value is

needed for the 64-bit event bitmap, but using it to identify command events

aliases event codes above 0x3f. In particular, Synchronous Train Complete

(0x4f) was treated as Command Status (0x0f) even though its payload has no

opcode.

Reject actual command events that are too short for the field being

inspected. A truncate

/// 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