CVE-2025-64666
High
Description
Improper input validation in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
SeverityHigh
CVSS7.5
Exploit probability—
Product
Microsoft Exchange Server
PublishedDec 9, 2025
First seenDec 9, 2025
Weakness typeCWE-20Improper input validation
How to fix
Update
- microsoft exchange_server_subscription_edition15.02.2562.035 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft exchange_server | 2016, 2019 | — |
| microsoft exchange_server_subscription_edition | v < 15.02.2562.035 | 15.02.2562.035 |
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