ZDI-21-822: (Pwn2Own) Microsoft Exchange Server PowerShell Improper Authentication Remote Code Execution Vulnerability
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Microsoft Exchange Server. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the Powershell service. The issue results from the lack of proper validation of a access token prior to executing the Exchange PowerShell command. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of SYSTEM.
| Affected Software | Affected Version | How to fix |
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Reference Links
Frequently Asked Questions
What is the severity of ZDI-21-822?
The severity of ZDI-21-822 is critical due to its potential for remote code execution without proper authentication.
How do I fix ZDI-21-822?
To fix ZDI-21-822, it is essential to apply the latest security updates provided by Microsoft for Exchange Server.
What systems are affected by ZDI-21-822?
ZDI-21-822 affects installations of Microsoft Exchange Server that are running vulnerable versions.
Can ZDI-21-822 be exploited without authentication?
No, ZDI-21-822 requires authentication, but the existing authentication mechanism can be bypassed.
What type of vulnerability is ZDI-21-822?
ZDI-21-822 is a remote code execution vulnerability that allows attackers to execute arbitrary code on affected systems.
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