What is CVE-2025-39954?

CVE-2025-39954 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a Divide By Zero flaw (CWE-369), affecting Linux kernel versions from 6.15 onward and patched in 6.16.9 and 6.17. CVE-2025-39954 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2025-39954?

CVE-2025-39954 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-2025-39954?

Yes, CVE-2025-39954 has been patched. Fixed versions include 6.16.9 and 6.17. If you are running Linux kernel 6.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2025-39954 actively exploited?

CVE-2025-39954 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Divide By Zero (CWE-369)?

The product divides a value by zero, causing a crash or unexpected behaviour. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/369.html

CVE-2025-39954

Medium

In the Linux kernel, the following vulnerability has been resolved: clk: sunxi-ng: mp: Fix dual-divider clock rate readback When dual-divider clock support was introduced, the P divider offset was left out of the .recalc_rate readback function. This causes the clock rate to become bogus or even zero (possibly due to the P divider being 1, leading to a divide-by-zero). Fix this by incorporating the P divider offset into the calculation.

Package Linux Kernel

Published 2025-10-09

Last modified 2026-02-26

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

Weakness type

CWE-369

CVE-2025-39954 is a Divide By Zero vulnerability

What is Divide By Zero?

The product divides a value by zero, causing a crash or unexpected behaviour. Learn more on MITRE CWE

Affected versions

Linux kernel versions 6.15 and later are affected. Fixed in 6.16.9, 6.17 and their respective stable series.

Affected from

≥ 6.15

Fixed in

✓ 6.16.9 6.16.x ✓ 6.17

References

The following references provide additional information about CVE-2025-39954 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/25fbbaf515acd13399589bd5ee6de5f35740cef2
Patch
Kernel patch commit
https://git.kernel.org/stable/c/40108f69c372af3aea73e7829d6849a44638d662
Patch

Details

CVE ID CVE-2025-39954

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2025-10-09

Modified 2026-02-26

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2025-39954?

CVE-2025-39954 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a Divide By Zero flaw (CWE-369) . It affects Linux kernel versions from 6.15 onward and has been patched in 6.16.9 and 6.17. CVE-2025-39954 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2025-39954?

CVE-2025-39954 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-2025-39954?

Yes — CVE-2025-39954 has been patched. Fixed versions include 6.16.9 and 6.17. If you are running Linux kernel 6.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2025-39954 actively exploited?

No — CVE-2025-39954 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is Divide By Zero (CWE-369)?

The product divides a value by zero, causing a crash or unexpected behaviour. View CWE-369 on MITRE CWE →