CVE Watch19 de ago. de 2026

CVE-2021-26855

Microsoft Exchange Server Remote Code Execution Vulnerability

CVSS

9.1

Crítica

EPSS

100.0%

p100

KEV

SIM

3 de nov. de 2021

Exploit Today

0-100

Publicado: 3 de mar. de 2021 · Última mod.: 19 de ago. de 2026 · CWE-918

EPSS · 30d

100.0%EPSS · 30 dias100.0%

2026-10-082026-11-05

Ficha do catálogo KEV

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-2021-26855

Descrição técnica

Microsoft Exchange Server Remote Code Execution Vulnerability

Referências oficiais

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