What is CVE-2025-21944?

CVE-2025-21944 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a Improper Locking flaw (CWE-667). CVE-2025-21944 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2025-21944?

CVE-2025-21944 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2025-21944?

No patch is currently available for CVE-2025-21944. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2025-21944 actively exploited?

CVE-2025-21944 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Improper Locking (CWE-667)?

The product does not properly acquire or release a lock, which can lead to unexpected behaviour. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/667.html

CVE-2025-21944

Medium

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix bug on trap in smb2_lock If lock count is greater than 1, flags could be old value. It should be checked with flags of smb_lock, not flags. It will cause bug-on trap from locks_free_lock in error handling routine.

Package Linux Kernel

Published 2025-04-01

Last modified 2025-11-03

CVSS version 3.1

Patch available

Awaiting data

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

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

Weakness type

CWE-667

CVE-2025-21944 is a Improper Locking vulnerability

What is Improper Locking?

The product does not properly acquire or release a lock, which can lead to unexpected behaviour. Learn more on MITRE CWE

References

The following references provide additional information about CVE-2025-21944 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Debian Security
https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html
Kernel patch commit
https://git.kernel.org/stable/c/11e0e74e14f1832a95092f2c98ed3b99f57797ee
Patch
Kernel patch commit
https://git.kernel.org/stable/c/2b70e3ac79eacbdf32571f7af48dd81cdd957ca8
Patch
Kernel patch commit
https://git.kernel.org/stable/c/8994f0ce8259f812b4f4a681d8298c6ff682efaa
Patch

5 patch commits total View all on NVD

Details

CVE ID CVE-2025-21944

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2025-04-01

Modified 2025-11-03

KEV No

Patch Awaiting data

Package linux

Frequently asked questions

What is CVE-2025-21944?

CVE-2025-21944 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as an Improper Locking flaw (CWE-667) . CVE-2025-21944 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2025-21944?

CVE-2025-21944 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2025-21944?

No patch is currently available for CVE-2025-21944. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2025-21944 actively exploited?

No — CVE-2025-21944 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is Improper Locking (CWE-667)?

The product does not properly acquire or release a lock, which can lead to unexpected behaviour. View CWE-667 on MITRE CWE →