CVE-2026-64513: KVM: x86: Unconditionally recompute CR8 intercept on PPR update

highCVSS 8.4CVE-2026-64513

CSIRTS triage

Other

What: The vulnerability involves unconditionally recomputing the CR8 intercept on PPR updates in KVM for x86.
Who is affected: Users of KVM on x86 architecture are affected.
Urgency: Remediation is important to ensure proper handling of PPR updates.
Action: Apply the fix for CR8 intercept recomputation on PPR updates.

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

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 8.4
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64513

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-2026-645130.17% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 7% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-64513	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

unknownCVE-2026-64513: In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Unconditionally …nvd

Recent advisories for KVM

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