CVE intelligence

CVE-2026-40226

Vulnerability intelligence

Published Apr 10, 2026Sources checked Nov 12, 2026

6.4MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-40226 and is rated Medium severity with a CVSS score of 6.4. 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: Sep 25, 2026

CBL-Mariner Releases Release Notes

Vendor-listed releases

255-28
255-30

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-40226?

In nspawn in systemd 233 through 259 before 260, an escape-to-host action can occur via a crafted optional config file.

Source: NVD