What is CVE-2026-89456?

CVE-2026-89456 is a High severity Linux kernel vulnerability with a CVSS score of 7.0 out of 10, affecting Linux kernel versions from 5.4.26 onward and patched in 5.10.270, 5.15.221, 6.1.188 and others. CVE-2026-89456 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89456?

CVE-2026-89456 has a CVSS score of 7.0 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-89456?

Yes, CVE-2026-89456 has been patched. Fixed versions include 5.10.270, 5.15.221, 6.1.188 and others. If you are running Linux kernel 5.4.26 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-89456 actively exploited?

CVE-2026-89456 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89456

High

In the Linux kernel, the following vulnerability has been resolved: s390/dasd: Propagate partial completion length across ERP recovery dasd_default_erp_postaction() copies the timing and device state from the finished ERP request back to the original request but drops proc_bytes. A request that was partially completed, an ESE read of a not-yet-allocated track returns fewer bytes than requested, and then recovered through the ERP chain loses its partial-completion length. __dasd_cleanup_cqr() then sees proc_bytes == 0 and completes the whole request instead of requeueing the remainder, silently returning zeroed data for the part that was never read. Carry proc_bytes over to the original request like the other per-request state.

Package Linux Kernel

Published 2026-09-11

Last modified 2026-09-14

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.0

out of 10

High

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 5.4.26, 5.5.10, 5.6 and later are affected. Fixed in 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.109, 6.18.50, 7.2.4, 7.3-rc1 and their respective stable series.

Affected from

≥ 5.4.26 ≥ 5.5.10 ≥ 5.6

Fixed in

✓ 5.10.270 5.10.x ✓ 5.15.221 5.15.x ✓ 6.1.188 6.1.x ✓ 6.6.157 6.6.x ✓ 6.12.109 6.12.x ✓ 6.18.50 6.18.x ✓ 7.2.4 7.2.x ✓ 7.3-rc1

References

8 total

Showing 5 of 8 references View all on NVD

Details

CVE ID CVE-2026-89456

Severity High

CVSS score 7.0 / 10

CVSS version 3.1

Published 2026-09-11

Modified 2026-09-14

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-89456?

CVE-2026-89456 is a High severity Linux kernel vulnerability with a CVSS score of 7.0 out of 10 . It affects Linux kernel versions from 5.4.26 onward and has been patched in 5.10.270, 5.15.221, 6.1.188 and others. CVE-2026-89456 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89456?

CVE-2026-89456 has a CVSS score of 7.0 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:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-89456?

Yes. CVE-2026-89456 has been patched. Fixed versions include 5.10.270, 5.15.221, 6.1.188 and others. If you are running Linux kernel 5.4.26 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-89456 actively exploited?

No. CVE-2026-89456 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.