{"schema":"threatline.record/2","record":{"id":"CVE-2021-42321","aliases":[],"summary":"Microsoft Exchange Server Remote Code Execution Vulnerability","details":"An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution.","categories":["Applications & CMS"],"product":"Exchange","vendor":"Microsoft","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-42321","source_modified_at":"2026-08-19T16:27:07.165Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Microsoft Exchange Server 2016 Cumulative Update 21","vendor":"Microsoft","versions":[{"version":"15.01.0","lessThan":"15.01.2308.020","versionType":"custom","status":"affected"}],"defaultStatus":null},{"source":"CVE 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