Microsoft Exchange Server Remote Code Execution Vulnerability
CVE-2021-34473

9.1CRITICAL

Key Information:

Vendor: Microsoft
Status: Microsoft Exchange Server 2013 Cumulative Update 23; Microsoft Exchange Server 2019 Cumulative Update 9; Microsoft Exchange Server 2016 Cumulative Update 20; Microsoft Exchange Server 2016 Cumulative Update 19
Vendor: CVE Published:; 14 July 2021

Badges

💰 Ransomware👾 Exploit Exists🟡 Public PoC🟣 EPSS 94%🦅 CISA Reported

What is CVE-2021-34473?

Microsoft Exchange Server Remote Code Execution Vulnerability

CISA has reported CVE-2021-34473

CISA provides regional cyber and physical services to support security and resilience across the United States. CISA monitor the most dangerious vulnerabilities and have identifed CVE-2021-34473 as being exploited and is known by the CISA as enabling ransomware campaigns.

The CISA's recommendation is: Apply updates per vendor instructions.

Affected Version(s)

Microsoft Exchange Server 2013 Cumulative Update 23 x64-based Systems 15.00.0 < 15.00.1497.015

Microsoft Exchange Server 2016 Cumulative Update 19 x64-based Systems 15.01.0 < 15.01.2176.012

Microsoft Exchange Server 2016 Cumulative Update 20 x64-based Systems 15.01.0 < 15.01.2242.008

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

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