CVE-2026-40372

Microsoft Asp.net Core vulnerability

9.1 CRITICALEPSS 0.82%

Published21 Apr 2026

Description

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

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected products

Microsoft Asp.net Core≥ 10.0.0 < 10.0.7

Remediation

Fixed in

Microsoft Asp.net Core≥ 10.0.7

Patch & vendor advisories

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2026-40372 being actively exploited?

CVE-2026-40372 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.82%.

How severe is CVE-2026-40372?

CVE-2026-40372 has a CVSS 3.1 base score of 9.1, rated critical. EPSS estimates a 0.82% probability of exploitation.

Which products are affected by CVE-2026-40372?

Affected products include Microsoft Asp.net Core.

How do I fix CVE-2026-40372?

Upgrade affected software to a fixed version, for example Microsoft Asp.net Core 10.0.7 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-40372 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.