What is CVE-2026-3842?

CVE-2026-3842 is a security advisory published by Microsoft Security Response Center (MSRC) with High severity. Qemu-kvm: hyperv/syndbg: missing mapped-length guard after cpu_physical_memory_map causes host oob write

Which CVE IDs does CVE-2026-3842 cover?

CVE-2026-3842 covers the following CVE IDs: CVE-2026-3842. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-3842?

CVE-2026-3842 has a CVSS v3 base score of 7.8, published by Microsoft Security Response Center (MSRC).

Which products are affected by CVE-2026-3842?

CVE-2026-3842 affects 1 product, including: azl3 qemu 9.1.0-10 on Azure Linux 3.0.

CVE-2026-3842HighCVSS 7.8

Qemu-kvm: hyperv/syndbg: missing mapped-length guard after cpu_physical_memory_map causes host oob write

Vendor

Microsoft Security Response Center (MSRC)

Published

July 23, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-3842 →

🎯 Affected products1

azl3 qemu 9.1.0-10 on Azure Linux 3.0

✅ Remediation

KBCBL-Mariner Releases (Security Update) — fixed build 9.1.0-11

🔗 References (2)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-3842
referencehttps://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade