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Microsoft CVE-2021-26858: Microsoft Exchange Server Remote Code Execution Vulnerability (HAFNIUM Exploited)

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Microsoft CVE-2021-26858: Microsoft Exchange Server Remote Code Execution Vulnerability (HAFNIUM Exploited)

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
03/02/2021
Created
03/03/2021
Added
03/02/2021
Modified
12/01/2023

Description

There exists a post-authentication arbitrary file write vulnerability in Exchange. If HAFNIUM could authenticate with the Exchange server then they could use this vulnerability to write a file to any path on the server. They could authenticate by exploiting the CVE-2021-26855 SSRF vulnerability or by compromising a legitimate admin’s credentials.

Solution(s)

  • msft-kb5000871-22fec8f5-e504-4971-a880-88bab21a1f37
  • msft-kb5000871-28c56acf-f5f1-4a92-900d-0de0c58d61a4
  • msft-kb5000871-82a6c7b8-34c1-4d23-879a-8b5963acc47d
  • msft-kb5000871-c6ed44ca-634b-4b5c-91ba-12232d8ec98e

References

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