What is CVE-2026-64004?

CVE-2026-64004 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 3.4 onward and patched in 5.10.259, 5.15.210, 6.1.176 and others. CVE-2026-64004 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-64004?

CVE-2026-64004 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-64004?

Yes, CVE-2026-64004 has been patched. Fixed versions include 5.10.259, 5.15.210, 6.1.176 and others. If you are running Linux kernel 3.4 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-64004 actively exploited?

CVE-2026-64004 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-64004

High

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.

Package Linux Kernel

Published 2026-07-19

Last modified 2026-07-30

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected versions

Linux kernel versions 3.4 and later are affected. Fixed in 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.93, 6.18.35, 7.0.12, 7.1 and their respective stable series.

Affected from

≥ 3.4

Fixed in

✓ 5.10.259 5.10.x ✓ 5.15.210 5.15.x ✓ 6.1.176 6.1.x ✓ 6.6.143 6.6.x ✓ 6.12.93 6.12.x ✓ 6.18.35 6.18.x ✓ 7.0.12 7.0.x ✓ 7.1

References

8 total

Showing 5 of 8 references View all on NVD

Details

CVE ID CVE-2026-64004

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-07-19

Modified 2026-07-30

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-64004?

CVE-2026-64004 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 3.4 onward and has been patched in 5.10.259, 5.15.210, 6.1.176 and others. CVE-2026-64004 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-64004?

CVE-2026-64004 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-64004?

Yes. CVE-2026-64004 has been patched. Fixed versions include 5.10.259, 5.15.210, 6.1.176 and others. If you are running Linux kernel 3.4 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-64004 actively exploited?

No. CVE-2026-64004 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.