CVE-2026-40358
High
Description
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
SeverityHigh
CVSS8.4
Exploit probability—
Product
Microsoft Office
PublishedMay 12, 2026
First seenMay 12, 2026
Weakness typeCWE-416Use after free
How to fix
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft office | 2016, 2019 | — |
| microsoft 365_apps | No range specified | — |
| microsoft office_long_term_servicing_channel | 2021, 2024 | — |
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