CVE-2026-64909: high-severity vulnerability in Microsoft 365 Apps for Enterprise
Microsoft Office Remote Code Execution Vulnerability
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.8epss 0.5%
Integer underflow (wrap or wraparound) in Microsoft Office allows an unauthorized attacker to execute code locally.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Affected products
Microsoft · Microsoft 365 Apps for EnterpriseMicrosoft · Microsoft Office 2016Microsoft · Microsoft Office 2019Microsoft · Microsoft Office 365 for MacMicrosoft · Microsoft Office LTSC 2021Microsoft · Microsoft Office LTSC 2024Microsoft · Microsoft Office LTSC for Mac 2021Microsoft · Microsoft Office LTSC for Mac 2024Related CVEs — Microsoft 365 Apps for Enterprise
In the same product, most dangerous first.
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