CVE intelligence

CVE-2026-90401

Vulnerability intelligence

Published Sep 17, 2026Sources checked Nov 3, 2026

7.1HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-90401 and is rated High severity with a CVSS score of 7.1. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-90401?

In the Linux kernel, the following vulnerability has been resolved:

md: remove REQ_NOWAIT support from raid1/10/456

REQ_NOWAIT support in md personalities that can block internally is fundamentally incomplete. While reads can avoid some blocking paths, write requests can still encounter cases where one mirror succeeds while another returns -EAGAIN.

At that point md cannot distinguish queue pressure from a real device failure, so it can neither record a bad block nor safely retry the write without REQ_NOWAIT, leaving mirrors with divergent data.

Rather than continue advertising REQ_NOWAIT support for personalities that cannot implement it correctly, remove it from raid1, raid10 and raid456. Keep REQ_NOWAIT for linear and raid0, which only remap bios to their underlying devices; stacked limits will still clear the feature if any component device lacks REQ_NOWAIT support.

Source: NVD