{"id":"CVE-2026-45498","published":"2026-05-20T13:16:36Z","modified":"2026-07-23T12:10:00Z","title":"Microsoft Defender Denial of Service Vulnerability","vendor":"Microsoft","product":"Defender","tier":"core","eol":null,"description":{"text":"Microsoft Defender Denial of Service Vulnerability","provenance":"source","from":"NVD"},"summary":{"text":"Microsoft Defender contains a denial-of-service flaw classified as uncontrolled resource consumption. 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https://nvd.nist.gov/vuln/detail/CVE-2026-45498","provenance":"source"},"vulncheckKev":{"dateAdded":"2026-05-19","exploitedFirstSeen":"2026-05-19","ransomware":false,"evidence":[{"url":"https://api.msrc.microsoft.com/cvrf/v3.0/cvrf/2026-May","date":"2026-05-19"},{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45498","date":"2026-05-19"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2026-05-20"}],"evidenceTotal":3,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 31, 2026","url":"https://otx.alienvault.com/pulse/6ae4aefab0c2191cecd41862","created":"2026-10-30"},{"name":"Actively_Exploited_Kev | Oct 30, 2026","url":"https://otx.alienvault.com/pulse/6ae35d889ea92b4ce19c2680","created":"2026-10-29"},{"name":"Actively_Exploited_Kev | Oct 29, 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2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"}],"provenance":"machine"},"cwes":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45498","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-45498","tags":["Third Party Advisory","US Government Resource"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Remote unauthenticated network attack on exposed service","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"Microsoft Defender Denial of Service Vulnerability","start":0,"end":50}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not 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expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2026-31102","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-31102","exploited":true,"exploitedSince":"2026-05-20","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":1,"skipped":0,"earliest":"2026-07-02","earliestUrl":"https://github.com/salihuahmad105-creator/Vulnerability-scanner","repos":[{"name":"salihuahmad105-creator/Vulnerability-scanner","url":"https://github.com/salihuahmad105-creator/Vulnerability-scanner","stars":0,"created":"2026-07-02"}]},"first":{"date":"2026-07-02","source":"PoC-in-GitHub","url":"https://github.com/salihuahmad105-creator/Vulnerability-scanner"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"ai"},{"stage":"primary","techniques":["T1499"],"provenance":"ai"}],"timeline":[{"date":"2026-05-19","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV 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