CVE-2026-55053: Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

PriorityP347high7.8CVSS 3.1

AVLACLPRNUIRSUCHIHAH

EPSS

0.30%

22.3th percentile

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

Affected

11 ranges

Vendor	Product	Version range	Fixed in
microsoft	excel	—	—
microsoft	microsoft_365_apps_for_enterprise	>= 16.0.1 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_excel_2016	>= 16.0.0.0 < 16.0.5561.1001	16.0.5561.1001
microsoft	microsoft_office_2019	>= 19.0.0 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_office_365_for_mac	>= 1.0.0 < 16.111.26071215	16.111.26071215
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
microsoft	microsoft_office_ltsc_for_mac_2021	>= 16.0.1 < 16.111.26071215	16.111.26071215
microsoft	microsoft_office_ltsc_for_mac_2024	>= 16.0.0 < 16.111.26071215	16.111.26071215
microsoft	office_online_server	< 16.0.10417.20175	16.0.10417.20175
microsoft	office_online_server	>= 16.0.0.0 < 16.0.10417.20175	16.0.10417.20175

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