CVE-2025-22126: Linux kernel · md: fix mddev uaf while iterating all_mddevs list
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 30 Oct 2026, 01:33 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Apr 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
AI-suggested
Users should monitor the official Linux kernel advisories for updates addressing CVE-2025-22126. Until a patch is applied, avoid running untrusted code with local privileges that could trigger md subsystem operations. Follow vendor guidance once available for official fixes.
Description
CVE-2025-22126 is a use-after-free (UAF) vulnerability in the Linux kernel's md (multiple device) subsystem. It occurs during iteration over the all_mddevs list in md_notify_reboot() and md_exit() functions, where a race condition can lead to dereferencing freed memory. The vulnerability has a high severity with a CVSS score of 7.8, impacting confidentiality, integrity, and availability. The issue arises from improper locking and reference counting during list iteration, which can cause unsafe memory access. The fix involves changing the iteration method and introducing a helper function to safely manage references and prevent premature freeing of mddev structures.
References
- nvd.nist.gov/vuln/detail/CVE-2025-22126 (opens in a new tab)
- git.kernel.org/stable/c/5462544ccbad3fc938a71b01fa5bd3a0dc2b750a (opens in a new tab)
- git.kernel.org/stable/c/8542870237c3a48ff049b6c5df5f50c8728284fa (opens in a new tab)
- git.kernel.org/stable/c/ca9f84de76723b358dfc0606668efdca54afc2e5 (opens in a new tab)
- git.kernel.org/stable/c/d69a23d8e925f8052d657652a6875ec2712c7e33 (opens in a new tab)
- git.kernel.org/stable/c/e2a9f73ee408a460f4c9dfe03b4741d6b11652b8 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/05/msg00045.html (opens in a new tab)