CVE-2026-66301: Microsoft Dynamics 365 (On-Premises) Information Disclosure Vulnerability

Overview

Severity

Medium (CVSS 6.5)

CVSS Vector

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

Category

Information Disclosure

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Aug

Released

2026-08-11

EPSS Score

1.00% (percentile: 61.1%)

Description

Exposure of sensitive information to an unauthorized actor in Microsoft Dynamics 365 (on-premises) allows an authorized attacker to disclose information over a network.

FAQ

What type of information could be disclosed by this vulnerability? The type of information that could be disclosed if an attacker successfully exploited this vulnerability is sensitive information.

Affected Products (1)

Microsoft Dynamics

• Microsoft Dynamics 365 (on-premises) version 9.1

Security Updates (1)

• Release Notes

Acknowledgments

<a href="https://twitter.com/hoangnx99">hoangha</a> with <a href="https://lab.viettelcybersecurity.com/">VCSLab of Viettel Cyber Security</a>

Revision History

• 2026-08-11: Information published.