CVE-2025-21745

MEDIUMNVD 5.55.5
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2025-02-27. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.5Exploit: NoneExposed: 0

A fix is available — apply it.

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().

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
EPSS
12.3%
KEV
Not listed

Published

February 27, 2025

Last Modified

July 14, 2026

Advisory Details (10)

Auto-updated Jul 14, 2026
Patch available.
generic Patch Available

[SECURITY] [DLA 4178-1] linux security update

https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
generic Patch Available

[SECURITY] [DLA 4102-1] linux-6.1 security update

https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
generic

blk-cgroup: Fix class @block_class's subsystem refcount leakage - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/ffb494f1e7a047bd7a41b13796fcfb08fe5beafb
generic

blk-cgroup: Fix class @block_class's subsystem refcount leakage - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d1248436cbef1f924c04255367ff4845ccd9025e
generic

blk-cgroup: Fix class @block_class's subsystem refcount leakage - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/993121481b5a87829f1e8163f47158b72679f309
generic

blk-cgroup: Fix class @block_class's subsystem refcount leakage - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/67c7f213e052b1aa6caba4a7e25e303bc6997126
generic

blk-cgroup: Fix class @block_class's subsystem refcount leakage - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/431b6ef2714be4d5babb802114987541a88b43b0
generic

blk-cgroup: Fix class @block_class's subsystem refcount leakage - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/38287f779b34dfe959b4b681e909f2d3d52b88be
generic

blk-cgroup: Fix class @block_class's subsystem refcount leakage - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2ce09aabe009453d641a2ceb79e6461a2d4f3876

Patch Availability(28)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-gcp-lts-22.04 (5.15.0.1083.79) @ jammy2026-05-21ubuntu
ubuntulinux-tools-fips (5.15.0.140.80) @ jammy2026-05-21ubuntu
ubuntulinux-virtual-hwe-24.04-edge (6.11.0-26.26) @ oracular2026-05-21ubuntu
ubuntulinux-virtual-hwe-20.04-edge (5.15.0.140.135) @ jammy2026-05-21ubuntu
ubuntulinux-tools-gcp-fips (5.15.0.1083.73) @ jammy2026-05-21ubuntu
ubuntulinux-tools-gcp-edge (5.15.0.1083.92~20.04.1) @ focal2026-05-21ubuntu
ubuntulinux-tools-nvidia-tegra-rt (5.15.0.1037.37) @ jammy2026-05-21ubuntu
ubuntulinux-tools-oracle-64k (6.11.0-1016.17) @ oracular2026-05-21ubuntu
ubuntulinux-tools-aws (6.11.0-1014.15) @ oracular2026-05-21ubuntu
ubuntulinux-tools-gke-5.15 (5.15.0.1081.80) @ jammy2026-05-21ubuntu
ubuntulinux-tools-aws-fips (5.15.0.1084.80) @ jammy2026-05-21ubuntu
ubuntulinux-tools-realtime (5.15.0.1084.88) @ jammy2026-05-21ubuntu
ubuntulinux-tools-azure-fips (5.15.0.1089.74) @ jammy2026-05-21ubuntu
ubuntulinux-virtual-hwe-20.04-edge (5.15.0.142.152~20.04.1) @ focal2026-05-21ubuntu
ubuntulinux-xilinx-zynqmp-tools-host (5.15.0-1050.54) @ jammy2026-05-21ubuntu
ubuntulinux-virtual-6.8 (6.8.0-64.67) @ noble2026-05-21ubuntu
ubuntulinux-tools-raspi-nolpae (5.15.0.1078.76) @ jammy2026-05-21ubuntu
ubuntulinux-tools-aws-edge (5.15.0.1084.91~20.04.1) @ focal2026-05-21ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-64.67~22.04.1) @ jammy2026-05-21ubuntu
ubuntulinux-tools-realtime-6.8.1 (6.8.1-1025.26) @ noble2026-05-21ubuntu
ubuntulinux-tools-lowlatency-hwe-20.04-edge (6.8.0-64.67.1) @ noble2026-05-21ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1029.30) @ noble2026-05-21ubuntu
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2026.27) @ noble2026-05-21ubuntu
ubuntulinux-tools-gcp-lts-24.04 (6.8.0-1033.35) @ noble2026-05-21ubuntu
ubuntulinux-tools-raspi-6.8 (6.8.0-1031.35) @ noble2026-05-21ubuntu
ubuntulinux-tools-azure-nvidia-lts-24.04 (6.8.0-1022.23) @ noble2026-05-21ubuntu
redhatkernel-0:5.14.0-611.5.1.el9_72025-11-11redhat
linuxKernel @ 5.10.235osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Additional Vendor Advisories

(23)

Data Freshness Timeline

(refreshed 10× in last 7d / 48× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 127 total refreshes for this CVE.

  1. 2026-07-22 14:07 UTCEPSS rescore
  2. 2026-07-22 14:07 UTCEPSS rescore
  3. 2026-07-21 15:24 UTCEPSS rescore
  4. 2026-07-20 17:07 UTCEPSS rescore
  5. 2026-07-19 14:30 UTCEPSS rescore
  6. 2026-07-19 14:30 UTCEPSS rescore
  7. 2026-07-19 02:28 UTCEPSS rescore
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  9. 2026-07-18 10:03 UTCEPSS rescore
  10. 2026-07-16 17:02 UTCEPSS rescore
  11. 2026-07-15 16:57 UTCEPSS rescore
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-15 01:59 UTCEPSS rescore
  14. 2026-07-14 13:19 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  15. 2026-07-14 13:11 UTCMITRE cvelistV5
  16. 2026-07-13 22:29 UTCEPSS rescore
  17. 2026-07-13 22:29 UTCEPSS rescore
  18. 2026-07-13 06:12 UTCEPSS rescore
  19. 2026-07-13 06:12 UTCEPSS rescore
  20. 2026-07-12 05:46 UTCEPSS rescore
  21. 2026-07-12 05:46 UTCEPSS rescore
  22. 2026-07-11 08:27 UTCEPSS rescore
  23. 2026-07-11 08:26 UTCEPSS rescore
  24. 2026-07-10 17:41 UTCOSV refresh
  25. 2026-07-09 19:09 UTCEPSS rescore
Show 75 more
  1. 2026-07-08 15:14 UTCEPSS rescore
  2. 2026-07-07 13:45 UTCEPSS rescore
  3. 2026-07-06 16:26 UTCEPSS rescore
  4. 2026-07-06 02:22 UTCEPSS rescore
  5. 2026-07-06 02:22 UTCEPSS rescore
  6. 2026-07-05 02:30 UTCEPSS rescore
  7. 2026-07-04 06:30 UTCEPSS rescore
  8. 2026-07-01 15:06 UTCEPSS rescore
  9. 2026-06-30 23:21 UTCEPSS rescore
  10. 2026-06-30 23:21 UTCEPSS rescore
  11. 2026-06-29 14:06 UTCEPSS rescore
  12. 2026-06-28 14:07 UTCEPSS rescore
  13. 2026-06-28 14:07 UTCEPSS rescore
  14. 2026-06-28 04:55 UTCEPSS rescore
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  16. 2026-06-27 03:08 UTCEPSS rescore
  17. 2026-06-27 03:08 UTCEPSS rescore
  18. 2026-06-25 13:49 UTCEPSS rescore
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  20. 2026-06-24 14:04 UTCEPSS rescore
  21. 2026-06-24 14:04 UTCEPSS rescore
  22. 2026-06-23 21:32 UTCEPSS rescore
  23. 2026-06-23 21:32 UTCEPSS rescore
  24. 2026-06-22 14:25 UTCEPSS rescore
  25. 2026-06-22 14:25 UTCEPSS rescore
  26. 2026-06-22 01:37 UTCOSV refresh
  27. 2026-06-21 14:56 UTCEPSS rescore
  28. 2026-06-21 14:56 UTCEPSS rescore
  29. 2026-06-21 01:59 UTCEPSS rescore
  30. 2026-06-21 01:59 UTCEPSS rescore
  31. 2026-06-19 19:25 UTCEPSS rescore
  32. 2026-06-19 19:25 UTCEPSS rescore
  33. 2026-06-18 17:52 UTCEPSS rescore
  34. 2026-06-18 17:52 UTCEPSS rescore
  35. 2026-06-17 17:52 UTCEPSS rescore
  36. 2026-06-16 17:52 UTCEPSS rescore
  37. 2026-06-16 17:52 UTCEPSS rescore
  38. 2026-06-15 17:48 UTCEPSS rescore
  39. 2026-06-14 23:17 UTCEPSS rescore
  40. 2026-06-13 22:59 UTCEPSS rescore
  41. 2026-06-12 23:11 UTCEPSS rescore
  42. 2026-06-11 13:59 UTCEPSS rescore
  43. 2026-06-10 22:18 UTCEPSS rescore
  44. 2026-06-10 13:22 UTCEPSS rescore
  45. 2026-06-08 14:16 UTCEPSS rescore
  46. 2026-06-08 14:16 UTCEPSS rescore
  47. 2026-06-07 15:24 UTCEPSS rescore
  48. 2026-06-07 15:24 UTCEPSS rescore
  49. 2026-06-06 13:47 UTCEPSS rescore
  50. 2026-06-06 13:47 UTCEPSS rescore
  51. 2026-06-05 22:46 UTCEPSS rescore
  52. 2026-06-05 22:46 UTCEPSS rescore
  53. 2026-06-05 06:10 UTCEPSS rescore
  54. 2026-06-05 06:10 UTCEPSS rescore
  55. 2026-06-04 13:11 UTCEPSS rescore
  56. 2026-06-04 13:11 UTCEPSS rescore
  57. 2026-06-03 18:09 UTCOSV refresh
  58. 2026-06-02 20:12 UTCEPSS rescore
  59. 2026-06-02 20:12 UTCEPSS rescore
  60. 2026-06-01 13:51 UTCEPSS rescore
  61. 2026-06-01 13:51 UTCEPSS rescore
  62. 2026-05-31 22:30 UTCEPSS rescore
  63. 2026-05-31 22:30 UTCEPSS rescore
  64. 2026-05-31 00:16 UTCEPSS rescore
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  66. 2026-05-29 13:44 UTCEPSS rescore
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  71. 2026-05-27 13:40 UTCEPSS rescore
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Frequently asked(5)

What is CVE-2025-21745?
CVE-2025-21745 is a medium vulnerability published on February 27, 2025. In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Fix class @block_class's subsystem refcount leakage blkcgfillrootiostats() iterates over @blockclass's devices by classdeviter_(init|next)(), but does not end iterating with classdeviter_exit(), so causes the class's…
When was CVE-2025-21745 disclosed?
CVE-2025-21745 was first published in the National Vulnerability Database on February 27, 2025, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2025-21745 actively exploited?
CVE-2025-21745 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 12.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2025-21745?
CVE-2025-21745 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2025-21745?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-21745, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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