CVE-2026-55009
High
Description
Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
SeverityHigh
CVSS7.8
Exploit probability—
Product
Microsoft Exchange Server
PublishedJul 14, 2026
First seenJul 14, 2026
Weakness typeCWE-502Deserialization of untrusted data
How to fix
Update
- microsoft exchange_server_subscription_edition15.02.2562.045 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft exchange_server | 2016, 2019 | — |
| microsoft exchange_server_subscription_edition | v < 15.02.2562.045 | 15.02.2562.045 |
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