CVE-2026-78511
High
Description
Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Microsoft 365
PublishedSep 8, 2026
First seenSep 8, 2026
Weakness typeCWE-122CWE-122
How to fix
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft microsoft_365 | No range specified | — |
| microsoft 365_apps | No range specified | — |
| microsoft office_2019 | No range specified | — |
| microsoft office_2021 | No range specified | — |
| microsoft office_2024 | No range specified | — |
| microsoft word | 2016 | — |
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