CVE-2026-55009

HIGH

Microsoft Exchange Server Elevation of Privilege Vulnerability

Title source: cna
STIX 2.1

Description

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

References (1)

Core 1
Core References
Vendor Advisory vendor-advisory patch
Microsoft Exchange Server Elevation of Privilege Vulnerability
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55009

Scores

CVSS v3 7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-502
Status published
Products (4)
Microsoft/Microsoft Exchange Server 2016 Cumulative Update 23 15.01.0.0 - 15.01.2507.071
Microsoft/Microsoft Exchange Server 2019 Cumulative Update 14 15.02.0.0 - 15.02.1544.043
Microsoft/Microsoft Exchange Server 2019 Cumulative Update 15 15.02.0.0 - 15.02.1748.048
Microsoft/Microsoft Exchange Server Subscription Edition RTM 15.02.0.0 - 15.02.2562.045
Published Jul 14, 2026
Tracked Since Jul 14, 2026