Medium 5.5Published Feb 26, 2025

CVE-2025-21745blk-cgroup: Fix class @block_class's subsystem refcount leakage

Updated under an hour ago (Oct 26, 2026, 4:23 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

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: 5.5 MEDIUM (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from ef45fe470e1e5410db4af87abc5d5055427945ac before ffb494f1e7a047bd7a41b13796fcfb08fe5beafb; from ef45fe470e1e5410db4af87abc5d5055427945ac before 38287f779b34dfe959b4b681e909f2d3d52b88be; from ef45fe470e1e5410db4af87abc5d5055427945ac before 431b6ef2714be4d5babb802114987541a88b43b0; from ef45fe470e1e5410db4af87abc5d5055427945ac before 993121481b5a87829f1e8163f47158b72679f309; from ef45fe470e1e5410db4af87abc5d5055427945ac before 2ce09aabe009453d641a2ceb79e6461a2d4f3876; from ef45fe470e1e5410db4af87abc5d5055427945ac before 67c7f213e052b1aa6caba4a7e25e303bc6997126; from ef45fe470e1e5410db4af87abc5d5055427945ac before d1248436cbef1f924c04255367ff4845ccd9025e	CNA record
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name)	all versions	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.5	CISA ADP
linux linux_kernel linux:linux_kernel	from 5.9 before 6.1.129; from 6.2 before 6.6.78; from 6.7 before 6.12.14; from 6.13 before 6.13.3	NVD

References

References

https://git.kernel.org/stable/c/ffb494f1e7a047bd7a41b13796fcfb08fe5beafb
https://git.kernel.org/stable/c/38287f779b34dfe959b4b681e909f2d3d52b88be
https://git.kernel.org/stable/c/431b6ef2714be4d5babb802114987541a88b43b0	patch
https://git.kernel.org/stable/c/993121481b5a87829f1e8163f47158b72679f309	patch
https://git.kernel.org/stable/c/2ce09aabe009453d641a2ceb79e6461a2d4f3876	patch
https://git.kernel.org/stable/c/67c7f213e052b1aa6caba4a7e25e303bc6997126	patch
https://git.kernel.org/stable/c/d1248436cbef1f924c04255367ff4845ccd9025e	patch
https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
https://cert-portal.siemens.com/productcert/html/ssa-019113.html
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The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.