SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-64004

In the Linux kernel, the following vulnerability has been resolved: net/iucv: fix locking in .getsockopt Mirror iucv_sock_setsockopt() and wrap the whole switch in lock_sock()/release_sock().

HIGH 7.8EPSS 0.13%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

In the Linux kernel, the following vulnerability has been resolved: net/iucv: fix locking in .getsockopt Mirror iucv_sock_setsockopt() and wrap the whole switch in lock_sock()/release_sock(). The pre-existing SO_MSGLIMIT-only lock becomes redundant and is removed. Any AF_IUCV HIPER user can potentially crash the kernel by racing recvmsg() with getsockopt(SO_MSGSIZE): the SO_MSGSIZE arm dereferences iucv->hs_dev->mtu after iucv_sock_close() (called from the racing recvmsg()) has set hs_dev to NULL, producing a NULL pointer dereference oops.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.13% probability · 3th percentile
CISA KEV
Not listed
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.