CVE-2021-34473

critical

Description

Microsoft Exchange Server Remote Code Execution Vulnerability

From the Tenable Blog

ProxyShell: Attackers Actively Scanning for Vulnerable Microsoft Exchange Servers (CVE-2021-34473)
ProxyShell: Attackers Actively Scanning for Vulnerable Microsoft Exchange Servers (CVE-2021-34473)

Published: 2021-08-09

Three vulnerabilities from DEVCORE researcher Orange Tsai could be chained to achieve unauthenticated remote code execution. Attackers are searching for vulnerable instances to exploit. Update August 23: The Analysis section has been updated with information about exploitation of this vulnerability chain. Organizations should update immediately.

References

http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34473

https://www.zerodayinitiative.com/advisories/ZDI-21-821/

Details

Source: Mitre, NVD

Published: 2021-07-14

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 9.1

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Severity: Critical