CVE-2021-34453: Microsoft Exchange Server Denial of Service Vulnerability

Overview

Severity

High (CVSS 7.5)

CVSS Vector

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

Category

Denial of Service

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2021-Oct

Released

2021-10-12

EPSS Score

8.39% (percentile: 92.3%)

Affected Products (4)

Server Software

• Microsoft Exchange Server 2019 Cumulative Update 11
• Microsoft Exchange Server 2019 Cumulative Update 10
• Microsoft Exchange Server 2016 Cumulative Update 21
• Microsoft Exchange Server 2016 Cumulative Update 22

Security Updates (4)

• 5007012
• 5007012
• 5007012
• 5007012

Acknowledgments

<a href="https://twitter.com/n_joly">Nicolas Joly</a> of Microsoft Corporation

Revision History

• 2021-10-12: Information published.