What is CVE-2025-21736?

CVE-2025-21736 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a Integer Overflow flaw (CWE-190), affecting Linux kernel versions from 2.6.38 onward and patched in 5.4.291, 5.10.235, 5.15.179 and others. CVE-2025-21736 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2025-21736?

CVE-2025-21736 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-2025-21736?

Yes, CVE-2025-21736 has been patched. Fixed versions include 5.4.291, 5.10.235, 5.15.179 and others. If you are running Linux kernel 2.6.38 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2025-21736 actively exploited?

CVE-2025-21736 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Integer Overflow (CWE-190)?

The product performs a calculation that can produce an integer overflow, leading to unexpected values. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/190.html

CVE-2025-21736

Medium

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix possible int overflows in nilfs_fiemap() Since nilfs_bmap_lookup_contig() in nilfs_fiemap() calculates its result by being prepared to go through potentially maxblocks == INT_MAX blocks, the value in n may experience an overflow caused by left shift of blkbits. While it is extremely unlikely to occur, play it safe and cast right hand expression to wider type to mitigate the issue. Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE.

Package Linux Kernel

Published 2025-02-27

Last modified 2025-11-03

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-190

CVE-2025-21736 is a Integer Overflow vulnerability

What is Integer Overflow?

The product performs a calculation that can produce an integer overflow, leading to unexpected values. Learn more on MITRE CWE

Affected versions

Linux kernel versions 2.6.38 and later are affected. Fixed in 5.4.291, 5.10.235, 5.15.179, 6.1.129, 6.6.78, 6.12.14, 6.13.3, 6.14 and their respective stable series.

Affected from

≥ 2.6.38

Fixed in

✓ 5.4.291 5.4.x ✓ 5.10.235 5.10.x ✓ 5.15.179 5.15.x ✓ 6.1.129 6.1.x ✓ 6.6.78 6.6.x ✓ 6.12.14 6.12.x ✓ 6.13.3 6.13.x ✓ 6.14

References

10 total

Kernel Git
https://git.kernel.org/stable/c/250423300b4b0335918be187ef3cade248c06e6a

Patch
Kernel Git
https://git.kernel.org/stable/c/6438ef381c183444f7f9d1de18f22661cba1e946

Patch
Kernel Git
https://git.kernel.org/stable/c/b9495a9109abc31d3170f7aad7d48aa64610a1a2

Patch
Kernel Git
https://git.kernel.org/stable/c/f2bd0f1ab47822fe5bd699c8458b896c4b2edea1

Patch
Kernel Git
https://git.kernel.org/stable/c/f3d80f34f58445355fa27b9579a449fb186aa64e

Patch

Showing 5 of 10 references View all on NVD

Details

CVE ID CVE-2025-21736

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2025-02-27

Modified 2025-11-03

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2025-21736?

CVE-2025-21736 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as an Integer Overflow flaw (CWE-190) . It affects Linux kernel versions from 2.6.38 onward and has been patched in 5.4.291, 5.10.235, 5.15.179 and others. CVE-2025-21736 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2025-21736?

CVE-2025-21736 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-2025-21736?

Yes. CVE-2025-21736 has been patched. Fixed versions include 5.4.291, 5.10.235, 5.15.179 and others. If you are running Linux kernel 2.6.38 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2025-21736 actively exploited?

No. CVE-2025-21736 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.