CVE-2025-71225 md: suspend array while updating raid_disks via sysfs
A race condition in the Linux kernel md driver allows out-of-bounds memory access during RAID disk updates, potentially leading to code execution or system crashes.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-71225?
CVE-2025-71225 is a medium-severity vulnerability in Linux kernel, published on 18 Feb 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
md: suspend array while updating raid_disks via sysfs
In raid1_reshape(), freeze_array() is called before modifying the r1bio memory pool (conf->r1bio_pool) and conf->raid_disks, and unfreeze_array() is called after the update is completed.
However, freeze_array() only waits until nr_sync_pending and (nr_pending - nr_queued) of all buckets reaches zero. When an I/O error occurs, nr_queued is increased and the corresponding r1bio is queued to either retry_list or bio_end_io_list. As a result, freeze_array() may unblock before these r1bios are released.
This can lead to a situation where conf->raid_disks and the mempool have already been updated while queued r1bios, allocated with the old raid_disks value, are later released. Consequently, free_r1bio() may access memory out of bounds in put_all_bios() and release r1bios of the wrong size to the new mempool, potentially causing issues with the mempool as well.
Since only normal I/O might increase nr_queued while an I/O error occurs, suspending the array avoids this issue.
Note: Updating raid_disks via ioctl SET_ARRAY_INFO already suspends the array. Therefore, we suspend the array when updating raid_disks via sysfs to avoid this issue too.
Which versions are affected by CVE-2025-71225?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-71225?
Apply the vendor's patch.
Is CVE-2025-71225 being exploited?
There is no known exploitation of CVE-2025-71225 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-77874, BELL-CVE-2025-71225, DEBIAN-CVE-2025-71225, GHSA-hr98-gm7c-926r, ROOT-OS-DEBIAN-11-CVE-2025-71225, ROOT-OS-DEBIAN-12-CVE-2025-71225 and 3 more.