CVE-2026-63945

Summary

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

Bluetooth: ISO: serialize iso_sock_clear_timer with socket lock

iso_sock_close() calls iso_sock_clear_timer() before acquiring lock_sock(sk).

iso_sock_clear_timer() reads iso_pi(sk)->conn twice without the socket lock held:

if (!iso_pi(sk)->conn)
    return;
cancel_delayed_work(&iso_pi(sk)->conn->timeout_work);

Concurrently, iso_conn_del() executes under lock_sock(sk) and calls iso_chan_del(), which sets iso_pi(sk)->conn to NULL and may result in the final reference to the connection being dropped:

CPU0                         CPU1
----                         ----
iso_sock_clear_timer()
  if (conn != NULL) ...      lock_sock(sk)
                               iso_chan_del()
                               iso_pi(sk)->conn = NULL
  cancel_delayed_work(conn)  /* NULL deref or UAF */

iso_pi(sk)->conn is not stable across the unlock window, causing a NULL pointer dereference or use-after-free.

Serialize iso_sock_clear_timer() with the socket lock by moving it inside lock_sock()/release_sock(), matching the pattern used in iso_conn_del() and all other call sites.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxccf74f2390d60a2f9a75ef496d2564abb478f46a < d9cbf7144ec589a3f0cc91f74a1a1af2d2b14afaaffected
LinuxLinuxccf74f2390d60a2f9a75ef496d2564abb478f46a < 35f68f36d9883d56dec21cf85f7556d4657fc393affected
LinuxLinuxccf74f2390d60a2f9a75ef496d2564abb478f46a < 996c2104d0726a8fe584f85b3d6327197374a348affected
LinuxLinuxccf74f2390d60a2f9a75ef496d2564abb478f46a < bc08c15746f25f41dd0508b25780d1e84acbb2efaffected
LinuxLinuxccf74f2390d60a2f9a75ef496d2564abb478f46a < 51cb9dcfdf9a1bccf312ab2ae4b62db629f7dcd5affected
LinuxLinuxccf74f2390d60a2f9a75ef496d2564abb478f46a < 4b5f8e608749b7e8fa386c6e4301cf9272595859affected
LinuxLinux6.0affected
LinuxLinux0 < 6.0unaffected
LinuxLinux6.1.176 <= 6.1.*unaffected
LinuxLinux6.6.143 <= 6.6.*unaffected
LinuxLinux6.12.93 <= 6.12.*unaffected
LinuxLinux6.18.35 <= 6.18.*unaffected
LinuxLinux7.0.12 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References