CVE-2026-90401: Linux kernel · md: remove REQ_NOWAIT support from raid1/10/456
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix has been implemented that removes REQ_NOWAIT support from the affected raid personalities (raid1, raid10, raid456) in the Linux kernel. Users should update to fixed versions of the linux-hwe-edge kernel to address this issue. Specific patched versions are not listed here, so users should consult their vendor or distribution advisories for the appropriate updated kernel versions.
Description
A vulnerability in the Linux kernel's md (multiple device) subsystem related to REQ_NOWAIT support in raid1, raid10, and raid456 has been resolved. The issue arises because REQ_NOWAIT support is fundamentally incomplete for md personalities that can block internally, causing potential data divergence between mirrors during write operations. The fix removes REQ_NOWAIT support from these raid types while retaining it for linear and raid0. The vulnerability affects specific versions of the linux-hwe-edge kernel.
References
- nvd.nist.gov/vuln/detail/CVE-2026-90401 (opens in a new tab)
- git.kernel.org/stable/c/3fe5b7c9fb72ccc29bfd0f955b124892af7e3674 (opens in a new tab)
- git.kernel.org/stable/c/9bb9504e2d8f3d22ef12d51c333dd499f402dc8f (opens in a new tab)
- ubuntu.com/security/CVE-2026-90401 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-90401 (opens in a new tab)
- git.kernel.org/linus/3fe5b7c9fb72ccc29bfd0f955b124892af7e3674 (opens in a new tab)