CVE-2026-64909

Microsoft Office Remote Code Execution Vulnerability

At a glance

Severity
HIGH 7.8
EPSS
EPSS 0.47 % · percentile 40 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
microsoft
NVD status
Analyzed

Description

Integer underflow (wrap or wraparound) in Microsoft Office allows an unauthorized attacker to execute code locally.

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Cmicrosoft
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HNVD · secure@microsoft.com (Secondary)

Weaknesses (CWE)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Microsoft · Microsoft 365 Apps for Enterpriseaffected 16.0.1 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office 2016affected 16.0.0 < 16.0.5565.1001
Microsoft · Microsoft Office 2019affected 19.0.0 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office 365 for Macaffected 1.0.0 < 16.112.26081010
Microsoft · Microsoft Office LTSC 2021affected 16.0.1 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office LTSC 2024affected 16.0.0 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office LTSC for Mac 2021affected 16.0.1 < 16.112.26081010
Microsoft · Microsoft Office LTSC for Mac 2024affected 16.0.0 < 16.112.26081010

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD