What is CVE-2026-63940?

CVE-2026-63940 is a security advisory published by Microsoft Security Response Center (MSRC) with High severity. KVM: SEV: Ignore Port I/O requests of length '0'

Which CVE IDs does CVE-2026-63940 cover?

CVE-2026-63940 covers the following CVE IDs: CVE-2026-63940. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-63940?

CVE-2026-63940 has a CVSS v3 base score of 7.7, published by Microsoft Security Response Center (MSRC).

Which products are affected by CVE-2026-63940?

CVE-2026-63940 affects 4 products, including: azl3 kernel 6.6.144.1-1 on Azure Linux 3.0; azl3 kernel 6.6.150.1-1 on Azure Linux 3.0; azl3 kernel 6.6.152.1-1 on Azure Linux 3.0; azl3 kernel 6.6.157.1-1 on Azure Linux 3.0.

CVE-2026-63940HighCVSS 7.7

KVM: SEV: Ignore Port I/O requests of length '0'

Vendor

Microsoft Security Response Center (MSRC)

Published

July 23, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-63940 →

🎯 Affected products4

azl3 kernel 6.6.144.1-1 on Azure Linux 3.0
azl3 kernel 6.6.150.1-1 on Azure Linux 3.0
azl3 kernel 6.6.152.1-1 on Azure Linux 3.0
azl3 kernel 6.6.157.1-1 on Azure Linux 3.0

✅ Remediation

KBRelease Notes (Security Update)

🔗 References (2)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-63940
referencehttps://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade