CVE-2025-21963

Medium

In the Linux kernel, the following vulnerability has been resolved: cifs: Fix integer overflow while processing acdirmax mount option User-provided mount parameter acdirmax of type u32 is intended to have an upper limit, but before it is validated, the value is converted from seconds to jiffies which can lead to an integer overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE.

Package Linux Kernel
Published 2025-04-01
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-2025-21963 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 5.12 and later are affected. Fixed in 5.15.180, 6.1.132, 6.6.84, 6.12.20, 6.13.8, 6.14 and their respective stable series.

Affected from
≥ 5.12
Fixed in
✓ 5.15.180 5.15.x ✓ 6.1.132 6.1.x ✓ 6.6.84 6.6.x ✓ 6.12.20 6.12.x ✓ 6.13.8 6.13.x ✓ 6.14

References

The following references provide additional information about CVE-2025-21963 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

6 patch commits total View all on NVD

Frequently asked questions

  • What is CVE-2025-21963?

    CVE-2025-21963 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 5.12 onward and has been patched in 5.15.180, 6.1.132, 6.6.84 and others. CVE-2025-21963 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2025-21963?

    CVE-2025-21963 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-2025-21963?

    Yes — CVE-2025-21963 has been patched. Fixed versions include 5.15.180, 6.1.132, 6.6.84 and others. If you are running Linux kernel 5.12 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2025-21963 actively exploited?

    No — CVE-2025-21963 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Integer Overflow (CWE-190)?

    The product performs a calculation that can produce an integer overflow, leading to unexpected values. View CWE-190 on MITRE CWE →

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