CVE-2026-55017: Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

PriorityP345high7.8CVSS 3.1

AVLACLPRNUIRSUCHIHAH

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
microsoft	microsoft_365_apps_for_enterprise	>= 16.0.1 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_office_2016	>= 16.0.0 < 16.0.5561.1000	16.0.5561.1000
microsoft	microsoft_office_2019	>= 19.0.0 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_office_ltsc_2021	>= 16.0.1 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_office_ltsc_2024	>= 16.0.0 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases

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