{"schema":"threatline.record/2","record":{"id":"CVE-2026-42897","aliases":[],"summary":"Microsoft Exchange Server Cross-Site Scripting Vulnerability","details":"Microsoft Exchange Server contains a cross-site scripting vulnerability during web page generation in Outlook Web Access and when certain interaction conditions are met, arbitrary JavaScript can be executed in the browser context.","categories":["Unclassified"],"product":"Microsoft","vendor":"Microsoft","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-42897","source_modified_at":"2026-08-10T15:14:02.885Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Microsoft Exchange Server 2016 Cumulative Update 23","vendor":"Microsoft","versions":[{"version":"15.01.0.0","lessThan":"15.01.2507.069","versionType":"custom","status":"affected"}],"defaultStatus":null},{"source":"CVE 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unavailable.","ransomware_campaign_use":"Unknown"},"epss":{"probability":0.00519,"percentile":0.43324,"score_date":"2026-10-23"},"published_at":"2026-05-14T17:00:36.515Z","modified_at":"2026-08-10T15:14:02.885Z","provenance":[{"source":"CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T17:00:09.9001Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-42897","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-08-10T15:14:02.885Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-42897","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CISA KEV","CVE List","EPSS"],"references":[{"url":"https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-42897","source":"CISA KEV"},{"url":"https://learn.microsoft.com/en-us/exchange/plan-and-deploy/post-installation-tasks/security-best-practices/exchange-emergency-mitigation-service","source":"CISA KEV"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42897","source":"CISA KEV"},{"source":"CVE List","url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42897","tags":["vendor-advisory","patch"]},{"source":"CVE List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-42897","tags":["government-resource"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"active","automatable":"no","technical_impact":"total","assessed_at":"2026-05-14T00:00:00+00:00"},"classification":{"method":"product-first software-layer 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