Code Injection in Microsoft Exchange Server - CVE-2021-34473
Published: July 13, 2021 / Updated: January 2, 2024
Vulnerability identifier: #VU54705
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-34473
CWE-ID: CWE-94
Exploitation vector: Remote access
Exploit availability:
The vulnerability is being exploited in the wild
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to improper input validation in the Microsoft Exchange Server. A remote attacker can send a specially crafted request and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
Microsoft Exchange Server
How to mitigate CVE-2021-34473
Install updates from vendor's website.
Links to Public Exploits and PoC-codes
- Exploit #9478 - CVE-2021-34473 (CVE-2021-34473 Microsoft Exchange Server Remote Code Execution Vulnerability) (January 2, 2024)
- Exploit #6712 - proxyshell (Proof of Concept for CVE-2021-34473, CVE-2021-34523, and CVE-2021-31207) (September 7, 2021)
- Exploit #6639 - Microsoft Exchange ProxyShell RCE (August 19, 2021)
- Exploit #6627 - CVE-2021-34473 (CVE-2021-34473 Microsoft Exchange Server Remote Code Execution Vulnerability) (August 16, 2021)
- Exploit #6615 - CVE-2021-34473-scanner (Scanner for CVE-2021-34473, ProxyShell, A Microsoft Exchange On-premise Vulnerability) (August 11, 2021)