SB2021110928 - Remote code execution in Microsoft Exchange Server



SB2021110928 - Remote code execution in Microsoft Exchange Server

Published: November 9, 2021 Updated: November 16, 2022

Security Bulletin ID SB2021110928
Severity
Critical
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Critical 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Input validation error (CVE-ID: CVE-2021-42321)

The vulnerability allows a remote user to compromise the affected system.

The vulnerability exists due to insufficient validation of cmdlet arguments. A remote user can run a specially crafted cmdlet and execute arbitrary commands on the system.

Note, the vulnerability is being actively exploited in the wild.


Remediation

Install update from vendor's website.