CVE-2026-64128

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

Bluetooth: ISO: drop ISO_END frames received without prior ISO_START

ISO data PDUs carry a packet-boundary flag indicating START, CONT, END

or SINGLE. The ISO_CONT branch of iso_recv() guards against a missing

ISO_START by checking conn->rx_len before touching conn->rx_skb, but

ISO_END does not.

If a peer sends an ISO_END as the first packet on a fresh ISO

connection, conn->rx_skb is still NULL and conn->rx_len is zero, so

skb_put(conn->rx_skb, ...) dereferences NULL and oopses. For BIS,

where receivers sync to a broadcaster without pairing, any broadcaster

on the air can trigger this.

Mirror the ISO_CONT check at the top of ISO_END so a stray end fragment

is logged and dropped instead of crashing the host.