ZDI-21-894: (Pwn2Own) Microsoft Exchange Server OAB Arbitrary File Write 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 OAB service. The issue results from the lack of proper validation of user-supplied data, which can allow arbitrary files write to OAB folders. An attacker can leverage this vulnerability to execute arbitrary code in the context of SYSTEM.
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Microsoft Exchange |
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Reference Links
Frequently Asked Questions
What is the severity of ZDI-21-894?
The severity of ZDI-21-894 is high due to its ability to allow remote code execution on affected Microsoft Exchange Server installations.
Who is affected by ZDI-21-894?
ZDI-21-894 affects installations of Microsoft Exchange Server that are susceptible to this vulnerability.
What is the impact of ZDI-21-894?
The impact of ZDI-21-894 is significant as it enables remote attackers to execute arbitrary code after bypassing existing authentication mechanisms.
How do I fix ZDI-21-894?
To address ZDI-21-894, users should apply the relevant security updates provided by Microsoft for Exchange Server.
Is authentication required to exploit ZDI-21-894?
Yes, authentication is required to exploit ZDI-21-894, but the existing mechanisms can be bypassed.
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