CVE-2026-87696

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

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87696	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23::::::
	cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14::::::
	cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15::::::
	cpe:2.3:a:microsoft:exchange_server_subscription_edition::::::::

History

27 Oct 2026, 17:01

Type	Values Removed	Values Added
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87696 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87696 - Patch, Vendor Advisory
CPE		cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:::::: cpe:2.3:a:microsoft:exchange_server_subscription_edition:::::::: cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:::::: cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14::::::
First Time		Microsoft exchange Server Microsoft exchange Server Subscription Edition Microsoft

13 Oct 2026, 19:21

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 19:21

Updated : 2026-10-27 17:01

NVD link : CVE-2026-87696

Mitre link : CVE-2026-87696

CVE.ORG link : CVE-2026-87696

JSON object : View

Products Affected

microsoft

exchange_server
exchange_server_subscription_edition

CWE

CWE-347

Improper Verification of Cryptographic Signature

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