CVE-2026-55128

Microsoft Word Remote Code Execution Vulnerability

At a glance

Use after free in Microsoft Office Word allows an unauthorized attacker to execute code locally.

Version	Score	Vector	Scored by
CVSS 3.1	HIGH 7.8	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	microsoft
CVSS 3.1	HIGH 7.8	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	NVD · secure@microsoft.com (Secondary)

CERTFR-2026-AVI-0872 — Multiples vulnérabilités dans les produits Microsoft · cert.ssi.gouv.fr
CERTFR-2026-AVI-0868 — Multiples vulnérabilités dans Microsoft Office · cert.ssi.gouv.fr

cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
cpe:2.3:a:microsoft:microsoft_365:-:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x86:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:macos:-:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:macos:-:*
cpe:2.3:a:microsoft:office_online_server:*:*:*:*:*:*:*:* < 16.0.10417.20175
cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:* < 16.0.19725.20434
cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:word:2016:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:word:2016:*:*:*:*:*:x86:*

Product	Versions
Microsoft · Microsoft 365 Apps for Enterprise	affected 16.0.1 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office 2019	affected 19.0.0 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office 365 for Mac	affected 1.0.0 < 16.111.26071215
Microsoft · Microsoft Office LTSC 2021	affected 16.0.1 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office LTSC 2024	affected 16.0.0 < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office LTSC for Mac 2021	affected 16.0.1 < 16.111.26071215
Microsoft · Microsoft Office LTSC for Mac 2024	affected 16.0.0 < 16.111.26071215
Microsoft · Microsoft SharePoint Enterprise Server 2016	affected 16.0.0 < 16.0.5561.1001
Microsoft · Microsoft SharePoint Server 2019	affected 16.0.0 < 16.0.10417.20175
Microsoft · Microsoft SharePoint Server Subscription Edition	affected 16.0.0 < 16.0.19725.20434
Microsoft · Microsoft Word 2016	affected 16.0.1 < 16.0.5561.1000

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