What is CVE-2026-89920?

CVE-2026-89920 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 4.13 onward and patched in 6.18.51, 7.2.5 and 7.3-rc1. CVE-2026-89920 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89920?

CVE-2026-89920 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H.

Is there a patch available for CVE-2026-89920?

Yes, CVE-2026-89920 has been patched. Fixed versions include 6.18.51, 7.2.5 and 7.3-rc1. If you are running Linux kernel 4.13 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-89920 actively exploited?

CVE-2026-89920 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89920

High

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Fix memory corruption by not reinjecting CK machine checks Channel-subsystem damage machine checks are for the host channel subsystem. The guest channel subsystem is emulated in the userspace VMM. There is no point in forwarding such machine checks into the guest. This also simplifies the machine check reinjection and avoids kfree of a stack variable as reported by sashiko. There might be still machine checks that have the ck bit set with another bit (like instruction damage), mask out the CK bit in s390_backup_mcck_info(), like the CP and ED bits already are.

Package Linux Kernel

Published 2026-09-16

Last modified 2026-09-16

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 4.13 and later are affected. Fixed in 6.18.51, 7.2.5, 7.3-rc1 and their respective stable series.

Affected from

≥ 4.13

Fixed in

✓ 6.18.51 6.18.x ✓ 7.2.5 7.2.x ✓ 7.3-rc1

References

3 total

Details

CVE ID CVE-2026-89920

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-09-16

Modified 2026-09-16

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-89920?

CVE-2026-89920 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 4.13 onward and has been patched in 6.18.51, 7.2.5 and 7.3-rc1. CVE-2026-89920 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89920?

CVE-2026-89920 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:H/PR:L/UI:N/S:C/C:H/I:H/A:H.
Is there a patch available for CVE-2026-89920?

Yes. CVE-2026-89920 has been patched. Fixed versions include 6.18.51, 7.2.5 and 7.3-rc1. If you are running Linux kernel 4.13 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-89920 actively exploited?

No. CVE-2026-89920 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.