{
  "cvss": 9.1,
  "datePublished": "2021-11-03",
  "dateUpdated": "2021-11-03",
  "description": "Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution. This vulnerability is part of the ProxyLogon exploit chain.",
  "dueDate": "2022-05-03",
  "id": "CVE-2021-26855",
  "kev_catalogs": [
    "cisa"
  ],
  "knownRansomwareCampaignUse": "Known",
  "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",
  "product": "Exchange Server",
  "requiredAction": "Apply updates per vendor instructions.",
  "severity": "CRITICAL",
  "source": "cisa_known_exploited",
  "title": "Microsoft Exchange Server Remote Code Execution Vulnerability",
  "vendor": "Microsoft"
}