CVE-2021-42321

Published: Nov 10, 2021

Modified: Oct 21, 2025

PUBLISHED

CVSS v3.1

8.8

HIGH

Microsoft Exchange Server Remote Code Execution Vulnerability

Vendor	Product	Versions
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 21	affected `15.01.0 - < 15.01.2308.020`
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 10	affected `15.02.0 - < 15.02.0792.019`
Microsoft	Microsoft Exchange Server 2016 Cumulative Update 22	affected `15.0.0 - < 15.01.2375.017`
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 11	affected `15.02.0 - < 15.02.0986.014`

CVSS v3.1 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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

x_refsource_MISC

x_refsource_MISC

x_refsource_MISC

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