All CVE records
CVE-2021-26855 — Microsoft Exchange Server Remote Code Execution Vulnerability
Known ransomware use
CISA KEV listed
Added November 3, 2021 Remediate by May 3, 2022
Description
Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution. This vulnerability is part of the ProxyLogon exploit chain.
Required action
Apply updates per vendor instructions.
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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