CVE-2026-40363: Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

PriorityP353high8.4CVSS 3.1

AVLACLPRNUINSUCHIHAH

EPSS

0.38%

30.9th percentile

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

Affected

13 ranges

Vendor	Product	Version range	Fixed in
microsoft	365_copilot	< 16.0.19822.20190	16.0.19822.20190
microsoft	microsoft_365_apps_for_enterprise	>= 16.0.1 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_office_2016	>= 16.0.0 < 16.0.5552.1000	16.0.5552.1000
microsoft	microsoft_office_2019	>= 19.0.0 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_office_for_android	>= 16.0.1 < 16.0.19822.20190	16.0.19822.20190
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 < 16.109.26051019	16.109.26051019
microsoft	microsoft_office_ltsc_for_mac_2024	>= 16.0.0 < 16.109.26051019	16.109.26051019
microsoft	office	—	—
microsoft	office	—	—
microsoft	office_long_term_servicing_channel	—	—
microsoft	office_long_term_servicing_channel	—	—

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