CVE-2026-55009

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

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

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-2026-55009	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

24 Jul 2026, 19:19

Type	Values Removed	Values Added
First Time		Microsoft Microsoft exchange Server Subscription Edition Microsoft exchange Server
CPE		cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:::::: cpe:2.3:a:microsoft:exchange_server_subscription_edition:::::::: cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_15:::::: cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14::::::
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55009 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55009 - Vendor Advisory

14 Jul 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-14 17:17

Updated : 2026-07-24 19:19

NVD link : CVE-2026-55009

Mitre link : CVE-2026-55009

CVE.ORG link : CVE-2026-55009

JSON object : View

Products Affected

microsoft

exchange_server
exchange_server_subscription_edition

CWE

CWE-502

Deserialization of Untrusted Data

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