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CVE-2021-31207

Microsoft Exchange Server Security Feature Bypass Vulnerability

Basic Information

CVE State
PUBLISHED
Reserved Date
April 14, 2021
Published Date
May 11, 2021
Last Updated
February 04, 2025
Vendor
Microsoft
Product
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, Microsoft Exchange Server 2019 Cumulative Update 8
Description
Microsoft Exchange Server Security Feature Bypass Vulnerability

CVSS Scores

CVSS v3.1

6.6 - MEDIUM

Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

SSVC Information

Exploitation
active
Technical Impact
total

Exploit Status

Exploited in the Wild
Yes (added 2021-11-03 00:00:00 UTC) Source
Used in Malware
Yes (added 2021-11-03 00:00:00 UTC) Source

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31207 https://www.zerodayinitiative.com/advisories/ZDI-21-819/ http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html

Known Exploited Vulnerability Information

Source Added Date
CISA 2021-11-03 00:00:00 UTC

Scanner Integrations

Scanner URL Date Detected
Metasploit https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/exchange_proxyshell_rce.rb 2025-04-29 11:01:37 UTC

Potential Proof of Concepts

Warning: These PoCs have not been tested and could contain malware. Use at your own risk.

exchange_proxyshell_rce

Type: metasploit • Created: Unknown

Metasploit module for CVE-2021-31207