CVE intelligence

CVE-2026-90309

Vulnerability intelligence

Published Sep 17, 2026Sources checked Nov 11, 2026

7.8HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-90309 and is rated High severity with a CVSS score of 7.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Oct 21, 2026

Release Notes

Vendor-listed releases

6.6.157.1-1

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-2026-90309?

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

RDMA/erdma: Hold CQ references when processing EQ events

EQ handlers look up CQs from dev->cq_xa and invoke CQ completion or error callbacks outside the xarray lock. erdma_destroy_cq() can erase the CQ from the xarray and free its queue buffer and doorbell record while a previously scheduled EQ handler is still using the CQ.

Add a CQ refcount and take a reference under the xarray lock with refcount_inc_not_zero(). Remove the CQ from the xarray before dropping the destroy-path reference, then wait for in-flight EQ users before releasing CQ resources.

Source: NVD