CVE-2026-97778
High
Description
Integer overflow or wraparound in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Microsoft 365
PublishedOct 13, 2026
First seenOct 13, 2026
Weakness typeCWE-190Integer overflow
How to fix
Update
- microsoft office_online_server16.0.10417.20228 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft microsoft_365 | No range specified | — |
| microsoft 365_apps | No range specified | — |
| microsoft office_2021 | No range specified | — |
| microsoft office_2024 | No range specified | — |
| microsoft office_online_server | v < 16.0.10417.20228 | 16.0.10417.20228 |
Check your version
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