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:
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:
Statement
This advisory is only used to describe a potential risk. NSFOCUS does not provide any commitment or promise on this advisory. NSFOCUS and the author will not bear any liability for any direct and/or indirect consequences and losses caused by transmitting and/or using this advisory. NSFOCUS reserves all the rights to modify and interpret this advisory. Please include this statement paragraph when reproducing or transferring this advisory. Do not modify this advisory, add/delete any information to/from it, or use this advisory for commercial purposes without permission from NSFOCUS.
About NSFOCUS
NSFOCUS, Inc., a global network and cyber security leader, protects enterprises and carriers from advanced cyber attacks. The company’s Intelligent Hybrid Security strategy utilizes both cloud and on-premises security platforms, built on a foundation of real-time global threat intelligence, to provide multi-layered, unified and dynamic protection against advanced cyber attacks.
NSFOCUS works with Fortune Global 500 companies, including four of the world’s five largest financial institutions, organizations in insurance, retail, healthcare, critical infrastructure industries as well as government agencies. NSFOCUS has technology and channel partners in more than 60 countries, is a member of both the Microsoft Active Protections Program (MAPP), and the Cloud Security Alliance (CSA).
A wholly owned subsidiary of NSFOCUS Technologies Group Co., Ltd., the company has operations in the Americas, Europe, the Middle East and Asia Pacific.
