CVE-2026-69355: Microsoft Exchange Server Remote Code Execution Vulnerability

Overview

Severity

High (CVSS 8.8)

CVSS Vector

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

Category

Remote Code Execution

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Sep

Released

2026-09-08

Description

External control of file name or path in Microsoft Exchange Server allows an authorized attacker to execute code over a network.

FAQ

How could an attacker exploit this vulnerability? An authenticated attacker with low-level access to an affected server could send a specially crafted request to execute code on the server. User interaction is not required.

Affected Products (4)

ESU

• Microsoft Exchange Server 2019 Cumulative Update 15
• Microsoft Exchange Server 2019 Cumulative Update 14
• Microsoft Exchange Server 2016 Cumulative Update 23

Server Software

• Microsoft Exchange Server Subscription Edition RTM

Security Updates (1)

• 5121608

Acknowledgments

<a href="https://x.com/xamroot">Max Toor</a> with Microsoft

Revision History

• 2026-09-08: Information published.