{"schemaVersion":3,"id":"CVE-2021-34464","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"Microsoft Defender Remote Code Execution Vulnerability","dates":{"published":"2021-07-16T20:19:52.000Z","modified":"2026-08-10T15:11:59.830Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.3,"severity":"high","version":"2.0","versionLabel":"v2.0","source":"NVD","vector":"AV:N/AC:M/Au:N/C:C/I:C/A:C","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":7.8,"severity":"high","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":7.8,"severity":"high","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":9.3,"severity":"high","vector":"AV:N/AC:M/Au:N/C:C/I:C/A:C","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.02643,"percentile":0.85376,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.02643},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.02643,"percentile":0.85376}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.02643,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.02643,"percentile":0.85376}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[],"affected":[{"vendor":"microsoft","product":"malware_protection_engine","name":"Malware Protection Engine","label":"malware_protection_engine","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"na","noFixRecorded":false,"fixedIn":null}],"versionsText":"na","eol":null,"hubHref":"/vendor/microsoft/malware_protection_engine"},{"vendor":"microsoft","product":"microsoft malware protection engine","name":"Microsoft Malware Protection Engine","label":"microsoft malware protection engine","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 1.1.0.0, < 1.1.18242.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 1.1.0.0, < 1.1.18242.0","eol":null,"hubHref":"/vendor/microsoft/microsoft_malware_protection_engine"}],"affectedCount":2,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34464","label":"msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34464","hostname":"msrc.microsoft.com","tags":["Vendor Advisory","Patch"]},{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34464","label":"portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34464","hostname":"portal.msrc.microsoft.com","tags":["X Refsource MISC","X Transferred","Patch","Vendor Advisory"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2021-07-16T20:19:52.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-08-10T15:11:59.830Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":70,"level":"high","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T18:13:51.310Z","stale":false,"partial":false}}