Microsoft Exchange Server Remote Code Execution Vulnerability (CVE-2020-16875) Threat Alert

Microsoft Exchange Server Remote Code Execution Vulnerability (CVE-2020-16875) Threat Alert

September 30, 2020 | Mina Hao

Overview

Microsoft has fixed a critical vulnerability in its September 2020 Security Updates, which is a remote code execution vulnerability (CVE-2020-16875) in Microsoft Exchange Server. Recently, relevant proof of concept (PoC) has appeared on the Internet.

Due to incorrect verification of cmdlet arguments, an attacker may trigger this vulnerability by sending an email that contains special cmdlet arguments to the affected Exchange server. An attacker who successfully exploited the vulnerability could execute arbitrary code with system privileges on the affected system. It is worth noting that the prerequisite for successfully exploiting the vulnerability is to have user rights that can be authenticated as an Exchange role.

Reference link:

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16875

Affected Versions

  • Microsoft Exchange Server 2016 Cumulative Update 16
  • Microsoft Exchange Server 2016 Cumulative Update 17
  • Microsoft Exchange Server 2019 Cumulative Update 5
  • Microsoft Exchange Server 2019 Cumulative Update 6  

Solution

Microsoft has fixed a critical vulnerability in its September 2020 Security Updates. Given the appearance of PoC, users are strongly advised to download the updates.

For more information, see Microsoft’s official security advisory at the following link:

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16875

Statement

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