CVE-2026-53125
What it is
In the Linux kernel, the following vulnerability has been resolved: md: fix array_state=clear sysfs deadlock When "clear" is written to array_state, md_attr_store() breaks sysfs active protection so the array can delete itself from its own sysfs store method. However, md_attr_store() currently drops the mddev reference before calling sysfs_unbreak_active_protection(). Once do_md_stop(..., 0) has made the mddev eligible for delayed deletion, the temporary kobject reference taken by sysfs_break_active_protection() can become the last kobject reference protecting the md kobject. That allows sysfs_unbreak_active_protection() to drop the last kobject reference from the current sysfs writer context. kobject teardown then recurses into kernfs removal while the current sysfs node is still being unwound, and lockdep reports recursive locking on kn->active with kernfs_drain() in the call chain. Reproducer on an existing level: 1. Create an md0 linear array and activate it: mknod /dev/md0 b 9 0 echo none > /sys/block/md0/md/metadata_version echo linear > /sys/block/md0/md/level echo 1 > /sys/block/md0/md/raid_disks echo "$(cat /sys/class/block/sdb/dev)" > /sys/block/md0/md/new_dev echo "$(($(cat /sys/class/block/sdb/size) / 2))" > \ /sys/block/md0/md/dev-sdb/size echo 0 > /sys/block/md0/md/dev-sdb/slot echo active > /sys/block/md0/md/array_state 2. Wait briefly for the array to settle, then clear it: sleep 2 echo clear > /sys/block/md0/md/array_state The warning looks like: WARNING: possible recursive locking detected bash/588 is trying to acquire lock: (kn->active#65) at __kernfs_remove+0x157/0x1d0 but task is already holding lock: (kn->active#65) at sysfs_unbreak_active_protection+0x1f/0x40 ... Call Trace: kernfs_drain __kernfs_remove kernfs_remove_by_name_ns sysfs_remove_group sysfs_remove_groups __kobject_del kobject_put md_attr_store kernfs_fop_write_iter vfs_write ksys_write Restore active protection before mddev_put() so the extra sysfs kobject reference is dropped while the mddev is still held alive. The actual md kobject deletion is then deferred until after the sysfs write path has fully returned.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-667
- Record status
- Analyzed
Affected
- Linux Kernel < 6.18.33
- Linux Kernel < 7.0.10
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-53125.md and follow it. Check whether this project is affected by CVE-2026-53125. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/2aa72276fab9851dbd59c2daeb4b590c5a113908
- https://git.kernel.org/stable/c/62c44566da7493ee48ef17e8507bb798338a07cb
- https://git.kernel.org/stable/c/92ad0ec509ffb188d8f849b63148664df37b4a52