{"schema":"threatline.record/2","record":{"id":"CVE-2023-21529","aliases":[],"summary":"Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability","details":"Microsoft Exchange Server contains a deserialization of untrusted data that allows an authenticated attacker to achieve remote code execution.","categories":["Applications & CMS"],"product":"Exchange Server","vendor":"Microsoft","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2023-21529","source_modified_at":"2026-08-19T16:26:33.854Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Microsoft Exchange Server 2013 Cumulative Update 23","vendor":"Microsoft","versions":[{"version":"15.00.0","lessThan":"15.00.1497.047","versionType":"custom","status":"affected"}],"defaultStatus":null},{"source":"CVE 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unavailable.","ransomware_campaign_use":"Known"},"epss":{"probability":0.59294,"percentile":0.9912,"score_date":"2026-10-23"},"published_at":"2023-02-14T19:33:00.590Z","modified_at":"2026-08-19T16:26:33.854Z","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-2023-21529","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-08-19T16:26:33.854Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2023-21529","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CISA KEV","CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21529","tags":["vendor-advisory","x_transferred"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-21529","source":"CISA KEV"},{"source":"CVE List","url":"https://www.microsoft.com/en-us/security/blog/2026/04/06/storm-1175-focuses-gaze-on-vulnerable-web-facing-assets-in-high-tempo-medusa-ransomware-operations/","tags":["vendor-advisory"]},{"source":"CVE List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-21529","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":"2023-02-15T00:00:00+00:00"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-08-19T16:26:33.854Z","content_hash":"e8f315dcd13bc73c97fbf40613f4f9d6c121ad0ecbfd7e4cab6d792e25d3307d"}}