CVE-2025-21745: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.3% chance of exploitation in the next 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().

Affected products

• Linux Linux Kernel: from 5.9, before 6.1.129 (fixed in 6.1.129); from 6.2, before 6.6.78 (fixed in 6.6.78); from 6.7, before 6.12.14 (fixed in 6.12.14); from 6.13, before 6.13.3 (fixed in 6.13.3)

Published 2025-02-27. Last modified 2026-07-14.