Vulnerability in Linux

CVE-2026-63946

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: fix UAF in iso_recv_frame iso_recv_frame reads conn->sk under iso_conn_lock but releases the lock before using sk, with no reference held. A concurrent iso_sock_kill() can free sk in that window, causing use-after-free on sk->sk_state and sock_queue_rcv_skb(). Fix by replacing the bare pointer read with iso_sock_hold(conn), which calls sock_hold() while the spinlock is held, atomically elevating the refcount before the lock drops. Add a drop_put label so sock_put() is called on all exit paths where the hold succeeded.

EPSS: 0.003 (26.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

  • Linux — versions ccf74f2390d60a2f9a75ef496d2564abb478f46a, 6.0, 0

References

Frequently asked questions

What is CVE-2026-63946?
CVE-2026-63946 is a high-severity vulnerability in Linux. CVSS score: 8.8/10. Published 2026-07-19.
How severe is CVE-2026-63946?
High severity. CVSS v3 base score is 8.8 out of 10.