CVE-2026-42831: Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

PriorityP348high7.8CVSS 3.1

AVLACLPRNUIRSUCHIHAH

EPSS

0.44%

35.5th percentile

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

Affected

6 ranges

Vendor	Product	Version range	Fixed in
microsoft	365_copilot	< 16.0.19822.20190	16.0.19822.20190
microsoft	microsoft_office_for_android	>= 16.0.1 < 16.0.19822.20190	16.0.19822.20190
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_long_term_servicing_channel	—	—

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