What is CVE-2025-21659?

CVE-2025-21659 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 6.8 onward and patched in 6.12.10 and 6.13. CVE-2025-21659 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2025-21659?

CVE-2025-21659 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-2025-21659?

Yes, CVE-2025-21659 has been patched. Fixed versions include 6.12.10 and 6.13. If you are running Linux kernel 6.8 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2025-21659 actively exploited?

CVE-2025-21659 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2025-21659

Medium

In the Linux kernel, the following vulnerability has been resolved: netdev: prevent accessing NAPI instances from another namespace The NAPI IDs were not fully exposed to user space prior to the netlink API, so they were never namespaced. The netlink API must ensure that at the very least NAPI instance belongs to the same netns as the owner of the genl sock. napi_by_id() can become static now, but it needs to move because of dev_get_by_napi_id().

Package Linux Kernel

Published 2025-01-21

Last modified 2025-10-15

CVSS version 3.1

Patch available

Yes

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

Affected versions

Linux kernel versions 6.8 and later are affected. Fixed in 6.12.10, 6.13 and their respective stable series.

Affected from

≥ 6.8

Fixed in

✓ 6.12.10 6.12.x ✓ 6.13

References

The following references provide additional information about CVE-2025-21659 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/b683ba0df11ff563cc237eb1b74d6adfa77226bf
Patch
Kernel patch commit
https://git.kernel.org/stable/c/d1cacd74776895f6435941f86a1130e58f6dd226
Patch

Details

CVE ID CVE-2025-21659

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2025-01-21

Modified 2025-10-15

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2025-21659?

CVE-2025-21659 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 6.8 onward and has been patched in 6.12.10 and 6.13. CVE-2025-21659 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2025-21659?

CVE-2025-21659 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-2025-21659?

Yes — CVE-2025-21659 has been patched. Fixed versions include 6.12.10 and 6.13. If you are running Linux kernel 6.8 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2025-21659 actively exploited?

No — CVE-2025-21659 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.