A security researcher has reported a critical remote code execution vulnerability in Exchange Server, which could allow an attacker to hijack a login session of an affected user and gain full control of the affected system.

Exchange Server is an email messaging system that is widely used by large companies. This server is installed on the majority of email domains. It is a widely used server and is a component of the most widely used email system, Microsoft Exchange Server.

An attacker can exploit this vulnerability by sending an email with malicious content to an affected Exchange Server user. The user has to open this email on a mobile phone or on a computer that is connected to the Exchange Server through a network.

Once the user’s system is compromised, the attacker can send emails as that user to any system on the Exchange Server. These emails will appear to come from the user’s previous system.

This vulnerability affects versions of Exchange Server 2016, Exchange Server 2019, and Exchange Server 2013.

Microsoft has acknowledged this vulnerability and has released software updates. While researchers have confirmed that this vulnerability is being actively exploited in the wild, Microsoft has not reported any active attacks against this vulnerability at the time of writing this article.
* At the time of publishing this article, the status of this vulnerability was marked as “Critical”.

How to protect yourself from this vulnerability?

Use strong passwords and avoid using the same ones for Exchange Server and other systems

This vulnerability is a remote code execution vulnerability and affects Exchange Server. If you use the same password for both your email account and your work email, you risk giving attackers access to your system. You should not use the same password for two different systems or accounts. A strong password with a long string of numbers, letters, and symbols is highly recommended.
To help protect yourself from this vulnerability, Microsoft has released software updates. You can download them by visiting the following Microsoft website:

Microsoft Exchange Server 2016, Exchange Server 2019 and Exchange Server 2013

Microsoft released patches for these versions at the time of publishing this article. The patch is available on Microsoft’s website and can be downloaded by clicking here. This patch is available for both Windows Server 2016 and Windows 10.

Microsoft has released software updates to address this vulnerability

Microsoft has released software updates to address this vulnerability.
Employees and systems administrators should ensure that the Microsoft Exchange Server is updated to the latest version.
Additionally, users should ensure their anti-malware software is active on their machines and their email servers are scanned for viruses.*

You can protect yourself by following these steps:
- Ensure your anti-malware software is active on your machines
- Update to the latest version of Exchange Server
- Scan your email servers for viruses*#

Install the latest software updates as soon as possible

The first thing that you want to do is install the latest software updates for your Exchange Server. Not doing so could leave your system vulnerable and make it easier for an attacker to exploit this vulnerability.

* As of publishing this article, Microsoft has not released a fix for this vulnerability.

Microsoft Exchange Server 2016/2019 Patch

Microsoft is currently releasing patches to protect against this vulnerability. If you are using Microsoft Exchange Server 2016, your organization should install the patch as soon as possible.
** You will also receive an automatic update if you are running Exchange Server 2019 in your environment.

If you are using Microsoft Exchange Server 2013, it is important that you upgrade to a later release of the server. For example, if you are on Exchange Server 2013 Service Pack 1 or later, you should upgrade to Exchange Server 2016.

How do I know which version of Microsoft Exchange Server I am running?
Microsoft provides instructions on how to find out which version of the Microsoft Exchange server is installed on your system. To find out which version of the server your system is running, open a Command Prompt and type "ExchangeVersion". The command will return a string that looks like "


Published on: 05/10/2022 21:15:00 UTC
Last modified on: 05/18/2022 18:12:00 UTC