CVE-2025-21734

High

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix copy buffer page size For non-registered buffer, fastrpc driver copies the buffer and pass it to the remote subsystem. There is a problem with current implementation of page size calculation which is not considering the offset in the calculation. This might lead to passing of improper and out-of-bounds page size which could result in memory issue. Calculate page start and page end using the offset adjusted address instead of absolute address.

Package Linux Kernel
Published 2025-02-27
Last modified 2025-11-03
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

7.8

out of 10
High
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness type

CWE-787

CVE-2025-21734 is a Out-of-bounds Write vulnerability

What is Out-of-bounds Write?

The product writes data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE

Affected versions

Linux kernel versions 5.2 and later are affected. Fixed in 6.1.129, 6.6.78, 6.12.14, 6.13.3, 6.14 and their respective stable series.

Affected from
≥ 5.2
Fixed in
✓ 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

The following references provide additional information about CVE-2025-21734 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2025-21734?

    CVE-2025-21734 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Out-of-bounds Write flaw (CWE-787) . It affects Linux kernel versions from 5.2 onward and has been patched in 6.1.129, 6.6.78, 6.12.14 and others. CVE-2025-21734 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2025-21734?

    CVE-2025-21734 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H .

  • Is there a patch available for CVE-2025-21734?

    Yes — CVE-2025-21734 has been patched. Fixed versions include 6.1.129, 6.6.78, 6.12.14 and others. If you are running Linux kernel 5.2 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2025-21734 actively exploited?

    No — CVE-2025-21734 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Out-of-bounds Write (CWE-787)?

    The product writes data past the end or before the beginning of the intended buffer. View CWE-787 on MITRE CWE →