CVE intelligence

CVE-2026-40372

Vulnerability intelligence

Published Apr 21, 2026Sources checked Nov 12, 2026

9.1CRITICALCVSS out of 10

What this means

Review the available evidence

CVE-2026-40372 and is rated Critical severity with a CVSS score of 9.1. 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: Apr 28, 2026

Release Notes Install KB5091596.

Vendor-listed releases

10.0.7
18.5.2

CISA KEVNot listedBased on the latest collected catalog

EPSS11.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-40372?

Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network.

Source: NVD