CVE-2026-63807: KVM: x86/mmu: Ensure hugepage is in by slot before checking max mapping level

highCVSS 8.8CVE-2026-63807

CSIRTS triage

vendor: KVM product: KVMOther

What: The vulnerability ensures that hugepage is in by slot before checking the maximum mapping level.
Who is affected: Deployments of KVM that utilize hugepages.
Urgency: Remediation is necessary to prevent potential issues related to memory management.
Action: Update to the latest version of KVM.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 8.8
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-63807

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-638070.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-63807	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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