{"id":"CVE-2019-0859","published":"2019-04-09T21:29:02Z","modified":"2026-06-17T02:09:03Z","title":"Microsoft Win32k Privilege Escalation Vulnerability","vendor":"Microsoft","product":"Win32k","tier":"core","eol":null,"description":{"text":"An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0685, CVE-2019-0803.","provenance":"source","from":"NVD"},"summary":{"text":"The flaw is an elevation of privilege vulnerability in Microsoft Windows, located in the Win32k component, which fails to properly handle objects in memory. An attacker with local access and low-privilege credentials, requiring no user interaction, can exploit it to gain elevated privileges on the affected system.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:07:27Z"},"cvss":{"score":7.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.04151,"percentile":0.90826,"date":"2026-10-28","provenance":"source"},"kev":{"dateAdded":"2021-11-03","dueDate":"2022-05-03","ransomware":true,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2019-0859","provenance":"source"},"vulncheckKev":{"dateAdded":"2019-03-17","exploitedFirstSeen":"2019-03-17","ransomware":true,"evidence":[{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2019-03-17"},{"url":"https://api.msrc.microsoft.com/cvrf/v3.0/cvrf/2019-Apr","date":"2019-04-09"},{"url":"https://blog.sonicwall.com/en-us/2019/12/top-cves-exploited-in-the-wild-in-the-year-2019/","date":"2019-12-27"},{"url":"https://securelist.com/magnitude-exploit-kit-evolution/97436/","date":"2020-06-24"},{"url":"https://cdn.pathfactory.com/assets/10753/contents/298161/03f15d14-01bb-462b-a8d4-d8c6149f5604.pdf","date":"2021-03-05"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2021-11-03"}],"evidenceTotal":6,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[],"references":[{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0859","tags":["Patch","Vendor Advisory"]},{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0859","tags":["Patch","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-0859","tags":["US Government Resource"]}],"techniques":[{"id":"T1068","name":"Exploitation for Privilege Escalation","tactics":["privilege-escalation"],"provenance":"source","basis":"ctid-cve","bases":["ctid-cve","ai-mapping"],"basisDetail":"CTID attack_to_cve (Phase 1); claude-haiku-5-5: Local privilege escalation via Win32k kernel component","mappingType":"uncategorized","evidence":[{"from":"description","quote":"An elevation of privilege vulnerability exists in Windows when the Win32k component","start":0,"end":83}],"confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2019-1610","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2019-1610","exploited":true,"exploitedSince":"2021-11-03","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":1,"skipped":0,"earliest":"2019-06-07","earliestUrl":"https://github.com/Sheisback/CVE-2019-0859-1day-Exploit","repos":[{"name":"Sheisback/CVE-2019-0859-1day-Exploit","url":"https://github.com/Sheisback/CVE-2019-0859-1day-Exploit","stars":117,"created":"2019-06-07"}]},"first":{"date":"2019-06-07","source":"PoC-in-GitHub","url":"https://github.com/Sheisback/CVE-2019-0859-1day-Exploit"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"related","techniques":["T1068"],"provenance":"source"}],"timeline":[{"date":"2019-03-17","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","provenance":"source"},{"date":"2019-04-09","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2019-0859","provenance":"source"},{"date":"2019-06-07","kind":"exploit-public","label":"First public exploit: PoC-in-GitHub","url":"https://github.com/Sheisback/CVE-2019-0859-1day-Exploit","provenance":"source"},{"date":"2021-11-03","kind":"kev","label":"Added to CISA KEV (known ransomware use)","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2021-11-03","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2019-1610","provenance":"source"}],"speed":{"daysToPublicExploit":59,"firstExploitFrom":"PoC-in-GitHub","daysToKev":939},"priority":{"score":76.6,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 2783 days ago"},{"name":"Known ransomware use","points":10.0,"detail":"CISA KEV and VulnCheck KEV: Known"},{"name":"EPSS percentile","points":18.17,"detail":"percentile 0.9083"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"1 PoC-in-GitHub repo"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":5.46,"detail":"base score 7.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]}}