Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2025-38621
Linux Linux — md: make rdev_addable usable for rcu mode
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U N N H 5.5 .0016 4.4 —
AFFECTED
Product Versions Fixed
Linux bc08041b32abe6c9824f78735bac22018eabfc06 – —
Linux 6.7 – 6.12.109
TIMELINE
Apr 16 Reserved by Linux
Aug 22 Published (CNA: Linux)
Sep 7 ENRICHED — CVE-2025-38621 (Linux). Received CVSS 5.5 and CPE data from NVD.
Description
In the Linux kernel, the following vulnerability has been resolved:
md: make rdev_addable usable for rcu mode
Our testcase trigger panic:
BUG: kernel NULL pointer dereference, address: 00000000000000e0
...
Oops: Oops: 0000 [#1] SMP NOPTI
CPU: 2 UID: 0 PID: 85 Comm: kworker/2:1 Not tainted 6.16.0+ #94
PREEMPT(none)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
Workqueue: md_misc md_start_sync
RIP: 0010:rdev_addable+0x4d/0xf0
...
Call Trace:
<TASK>
md_start_sync+0x329/0x480
process_one_work+0x226/0x6d0
worker_thread+0x19e/0x340
kthread+0x10f/0x250
ret_from_fork+0x14d/0x180
ret_from_fork_asm+0x1a/0x30
</TASK>
Modules linked in: raid10
CR2: 00000000000000e0
---[ end trace 0000000000000000 ]---
RIP: 0010:rdev_addable+0x4d/0xf0
md_spares_need_change in md_start_sync will call rdev_addable which
protected by rcu_read_lock/rcu_read_unlock. This rcu context will help
protect rdev won't be released, but rdev->mddev will be set to NULL
before we call synchronize_rcu in md_kick_rdev_from_array. Fix this by
using READ_ONCE and check does rdev->mddev still alive.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| April 16, 2025 | Reserved | Reserved by Linux |
| August 22, 2025 | Published | Published (CNA: Linux) |
| September 7, 2026 | ENRICHED | ENRICHED — CVE-2025-38621 (Linux). Received CVSS 5.5 and CPE data from NVD. |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | bc08041b32abe6c9824f78735bac22018eabfc06 | — |
| Linux | Linux | — | 6.7 | 6.12.109 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2025-38621 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.