Overview
What is CVE-2026-64909?
Integer underflow (wrap or wraparound) in Microsoft Office allows an unauthorized attacker to execute code locally.
CVE intelligence
CVE-2026-64909
Vulnerability intelligence
7.8HIGHCVSS out of 10
What this means
Review the available evidence
CVE-2026-64909 and is rated High severity with a CVSS score of 7.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
CISA KEVNot listedBased on the latest collected catalog
EPSS0.3%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships