What is CVE-2026-89677?

CVE-2026-89677 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.8 out of 10, affecting Linux kernel versions from 7.0 onward and patched in 7.2.4 and 7.3-rc1. CVE-2026-89677 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-89677?

CVE-2026-89677 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-2026-89677?

Yes, CVE-2026-89677 has been patched. Fixed versions include 7.2.4 and 7.3-rc1. If you are running Linux kernel 7.0 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-89677 actively exploited?

CVE-2026-89677 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-89677

Critical

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix possible fh_compose of wrong dentry in nfsd4_create_file() dentry_create() can hypothetically provide a different dentry than the one passed in. This could happen, for example, if the exported filesystem is NFS, and the server returned to OPEN a filehandle which matched a directory that was already in the dcache. Clearly this would not be expected! If this were to happen the dentry (child) that was already stored in resfhp could be freed and later dereferenced. We shouldn't call fh_compose() until we are certain that we have the final dentry, so this patch moved the fh_compose() call to two places: one for the case where the target already exists, and one after dentry_create() where it was created.

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 7.0 and later are affected. Fixed in 7.2.4, 7.3-rc1 and their respective stable series.

Affected from

≥ 7.0

Fixed in

✓ 7.2.4 7.2.x ✓ 7.3-rc1

References

2 total

Details

CVE ID CVE-2026-89677

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-2026-89677?

CVE-2026-89677 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.8 out of 10 . It affects Linux kernel versions from 7.0 onward and has been patched in 7.2.4 and 7.3-rc1. CVE-2026-89677 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-89677?

CVE-2026-89677 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-2026-89677?

Yes. CVE-2026-89677 has been patched. Fixed versions include 7.2.4 and 7.3-rc1. If you are running Linux kernel 7.0 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-89677 actively exploited?

No. CVE-2026-89677 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.