CVE-2021-42321: Microsoft Exchange Server Remote Code Execution Vulnerability
First published: Wed Nov 10 2021(Updated: )
An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution.
Credit: secure@microsoft.com secure@microsoft.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| =2016-cumulative_update_21 | ||
| =2016-cumulative_update_22 | ||
| =2019-cumulative_update_10 | ||
| =2019-cumulative_update_11 | ||
| Microsoft Exchange Server | =2016-cumulative_update_21 | |
| Microsoft Exchange Server | =2016-cumulative_update_22 | |
| Microsoft Exchange Server | =2019-cumulative_update_10 | |
| Microsoft Exchange Server | =2019-cumulative_update_11 | |
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Reference Links
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321
- http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html
- http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html
Frequently Asked Questions
What is CVE-2021-42321?
CVE-2021-42321 is a vulnerability in Microsoft Exchange Server that allows an authenticated attacker to perform remote code execution.
How does CVE-2021-42321 affect Microsoft Exchange Server?
CVE-2021-42321 affects Microsoft Exchange Server versions 2016 Cumulative Update 21, 2016 Cumulative Update 22, 2019 Cumulative Update 10, and 2019 Cumulative Update 11.
What is the severity of CVE-2021-42321?
CVE-2021-42321 has a severity rating of 8.8 (high).
How can an attacker exploit CVE-2021-42321?
An authenticated attacker can exploit CVE-2021-42321 by leveraging improper validation in cmdlet arguments within Microsoft Exchange to perform remote code execution.
Is there a fix available for CVE-2021-42321?
Yes, Microsoft has released security updates to address CVE-2021-42321. It is recommended to apply the latest Cumulative Updates for the affected versions of Microsoft Exchange Server.
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