CVSS8.8
Severityhigh
Weakness—
ExploitedNot in CISA KEV
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved: net/iucv: take a reference on the socket found in afiucv_hs_rcv() afiucv_hs_rcv() looks up the destination socket under iucv_sk_list.lock, drops the lock, and then passes the socket to the afiucv_hs_callback_*() handlers without holding a reference. AF_IUCV sockets are not RCU-protected and are freed synchronously by iucv_sock_kill() -> sock_put(), so a concurrent close can free the socket in the window between read_unlock() and the handler, which then dereferences freed memory (for example sk->sk_data_ready() in afiucv_hs_callback_syn()). Take a reference with sock_hold() while the socket is still on the list and release