CVE-2026-45503

Improper authorization in Microsoft Exchange Server allows an authorized attacker to disclose information over a network.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45503	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

No history.

Information

Published : 2026-06-09 17:17

Updated : 2026-07-28 23:16

NVD link : CVE-2026-45503

Mitre link : CVE-2026-45503

CVE.ORG link : CVE-2026-45503

JSON object : View

Products Affected

microsoft

exchange_server
exchange_server_subscription_edition

CWE

CWE-285

Improper Authorization

CWE-918

Server-Side Request Forgery (SSRF)

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