CVE-2026-50517
Critical
Description
Deserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.
SeverityCritical
CVSS9.9
Exploit probability—
Product
Microsoft 365 Copilot
PublishedJul 24, 2026
First seenJul 24, 2026
Weakness typeCWE-502Deserialization of untrusted data
How to fix
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft 365_copilot | No range specified | — |
Check your version
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