CVE-2026-87696 HIGH

CVE-2026-87696: Microsoft Exchange Server Elevation of Privilege Vulnerability

Vendor Microsoft
Product Microsoft Exchange Server 2016 Cumulative Update 23
Weakness CWE-347
Published October 13, 2026
Last update October 23, 2026
View on NVD All CVEs

CVSS base score

7.5/10
Attack vector Network
Attack complexity High
Privileges required Low
User interaction None
Confidentiality High
Integrity High

CVSS vector

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

What the vulnerability does

01Description

Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.

Key dates

02Disclosure timeline

October 13, 2026 CVE published
October 23, 2026 Record updated

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04Related CVE

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