What is CVE-2026-89681?

CVE-2026-89681 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.8 out of 10, affecting Linux kernel versions from 7.1 onward and patched in 7.2.4 and 7.3-rc1. CVE-2026-89681 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89681?

CVE-2026-89681 has a CVSS score of 9.8 out of 10, rated Critical severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-89681?

Yes, CVE-2026-89681 has been patched. Fixed versions include 7.2.4 and 7.3-rc1. If you are running Linux kernel 7.1 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-89681 actively exploited?

CVE-2026-89681 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89681

Critical

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix layout fence worker double-reference race The workqueue core clears WORK_STRUCT_PENDING before the callback is invoked, so delayed_work_pending() in lm_breaker_timedout() can return false while the fence worker is already running. This lets the breaker take a duplicate sc_count reference and schedule a new worker that coalesces with the in-progress one. The extra reference is never put, leaking the layout stateid. Replace the racy delayed_work_pending() check with an ls_fence_inflight boolean set atomically with refcount_inc_not_zero() under ls_lock, and cleared under ls_lock before the final nfs4_put_stid() on the dispose path; the retry path intentionally retains it. Remove the self-rearm mod_delayed_work() at the top of the worker.

Package Linux Kernel

Published 2026-09-11

Last modified 2026-09-13

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

9.8

out of 10

Critical

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 7.1 and later are affected. Fixed in 7.2.4, 7.3-rc1 and their respective stable series.

Affected from

≥ 7.1

Fixed in

✓ 7.2.4 7.2.x ✓ 7.3-rc1

References

2 total

Details

CVE ID CVE-2026-89681

Severity Critical

CVSS score 9.8 / 10

CVSS version 3.1

Published 2026-09-11

Modified 2026-09-13

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-89681?

CVE-2026-89681 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.8 out of 10 . It affects Linux kernel versions from 7.1 onward and has been patched in 7.2.4 and 7.3-rc1. CVE-2026-89681 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89681?

CVE-2026-89681 has a CVSS score of 9.8 out of 10, rated Critical severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-89681?

Yes. CVE-2026-89681 has been patched. Fixed versions include 7.2.4 and 7.3-rc1. If you are running Linux kernel 7.1 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-89681 actively exploited?

No. CVE-2026-89681 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.