CVE-2026-55009

No fix known EPSS 3%CVSS 7.8

Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.

Published 2026-07-14 · CVE record · OSV

Products: Microsoft Exchange Server 2016 Cumulative Update 23, Microsoft Exchange Server 2019 Cumulative Update 14, Microsoft Exchange Server 2019 Cumulative Update 15, Microsoft Exchange Server Subscription Edition RTM