{"id":"CVE-2021-33766","published":"2021-07-14T18:15:10Z","modified":"2026-08-10T19:58:44Z","title":"Microsoft Exchange Server Information Disclosure","vendor":"Microsoft","product":"Exchange Server","tier":"core","eol":null,"description":{"text":"Microsoft Exchange Server Information Disclosure Vulnerability","provenance":"source","from":"NVD"},"summary":{"text":"Microsoft Exchange Server contains an information disclosure vulnerability, classified under improper authentication, that affects the product as a whole. 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Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Network-exploitable public-facing Exchange server","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"Microsoft Exchange Server Information Disclosure Vulnerability","start":0,"end":62}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1005","name":"Data from Local System","tactics":["collection"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Information disclosure yields local data access","mappingType":"primary_impact","evidence":[{"from":"description","quote":"Microsoft Exchange Server Information Disclosure Vulnerability","start":0,"end":62}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, 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