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CVE-2021-26855 - Microsoft Exchange Server Remote Code Execution Vulnerability

Project:Microsoft

Product:Exchange Server

Date Added:2021-11-03Due Date:2021-04-16

Vulnerability Name

Microsoft Exchange Server Remote Code Execution Vulnerability

Description

Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution. This vulnerability is part of the ProxyLogon exploit chain.

Known To Be Used in Ransomware Campaigns?

Known

Action

Apply updates per vendor instructions.

Additional Notes

Reference CISA's ED 21-02 (https://www.cisa.gov/news-events/directives/ed-21-02-mitigate-microsoft-exchange-premises-product-vulnerabilities) for further guidance and requirements. Note: The due date for addressing this vulnerability aligns with the requirements outlined in ED 21-02. https://nvd.nist.gov/vuln/detail/CVE-2021-26855

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