CVE-2021-26858
Microsoft Exchange Server Remote Code Execution Vulnerability
CVSS
7.8
Alta
EPSS
93.7%
p100
KEV
SIM
3 de nov. de 2021
Exploit Today
80
0-100
Publicado: 3 de mar. de 2021 · Última mod.: 1 de out. de 2026
Produto
Microsoft / Exchange Server
Vulnerabilidade
Microsoft Exchange Server Remote Code Execution Vulnerability
Adicionado ao KEV
3 de nov. de 2021
Corrigir até
3 de mai. de 2022
Uso conhecido em ransomware
Sim
Descrição resumida
Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution. This vulnerability is part of the ProxyLogon exploit chain.
Ação necessária
Apply updates per vendor instructions.
Notas
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-2021-26858
Microsoft Exchange Server Remote Code Execution Vulnerability