CVE-2025-21745

Medium

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Fix class @block_class's subsystem refcount leakage blkcg_fill_root_iostats() iterates over @block_class's devices by class_dev_iter_(init|next)(), but does not end iterating with class_dev_iter_exit(), so causes the class's subsystem refcount leakage. Fix by ending the iterating with class_dev_iter_exit().

Package Linux Kernel
Published 2025-02-27
Last modified 2026-05-12
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 5.9 and later are affected. Fixed in 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
≥ 5.9
Fixed in
✓ 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

The following references provide additional information about CVE-2025-21745 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-2025-21745?

    CVE-2025-21745 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 5.9 onward and has been patched in 5.10.235, 5.15.179, 6.1.129 and others. CVE-2025-21745 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2025-21745?

    CVE-2025-21745 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-2025-21745?

    Yes — CVE-2025-21745 has been patched. Fixed versions include 5.10.235, 5.15.179, 6.1.129 and others. If you are running Linux kernel 5.9 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2025-21745 actively exploited?

    No — CVE-2025-21745 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.