{"id":"CVE-2019-0859","kind":"vulnerability","aliases":["CVE-2019-0859"],"related":[],"title":"Microsoft Win32k: Microsoft Win32k Privilege Escalation Vulnerability","description":"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.","summary":"Microsoft Win32k, the Windows kernel graphics driver, mishandles objects in memory, allowing privilege escalation. A local attacker who already has code running on the machine can run code in kernel mode, and CISA reports it exploited in the wild with known ransomware use.","severity":"high","cvss":7.8,"epss":0.04151,"exploited":true,"exploited_at":"2021-11-03T00:00:00+00:00","products":[{"name":"Microsoft Win32k","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","infrastructure","ransomware","self-hosted","windows"],"not_affected_if":["patched-windows"],"how_to_check":null,"fix":"Apply the Microsoft security update for CVE-2019-0859 per vendor instructions, as CISA requires; the specific KB or build is not in the sources.","status":"open","published_at":"2019-04-09T21:29:02+00:00","first_seen_at":"2026-10-23T19:11:53+00:00","triaged_at":"2026-10-23T21:39:47+00:00","updated_at":"2026-10-23T21:57:34+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-23T21:39:47Z","model":"claude-haiku-5-5","output":{"fix":"Apply the Microsoft security update for CVE-2019-0859 per vendor instructions, as CISA requires; the specific KB or build is not in the sources.","reach":"local","impact":"high","summary":"Microsoft Win32k, the Windows kernel graphics driver, mishandles objects in memory, allowing privilege escalation. A local attacker who already has code running on the machine can run code in kernel mode, and CISA reports it exploited in the wild with known ransomware use.","category":"infrastructure","who_cares":["windows","self-hosted"],"confidence":0.6,"needs_auth":"yes","worst_case":"local user gains kernel-mode code execution and full system control","analyst_note":"Find the Microsoft advisory for CVE-2019-0859 to confirm affected Windows builds, the KB numbers, and a check method; the sources only give the CISA KEV entry and EPSS score.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["patched-windows"],"user_interaction":"no","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000473,"input_tokens":2839,"output_tokens":379,"severity_before":"unknown"},"analyst_status":"queued","analyst_note":"Find the Microsoft advisory for CVE-2019-0859 to confirm affected Windows builds, the KB numbers, and a check method; the sources only give the CISA KEV entry and EPSS score.","search":"'-0685':99C '-0803':102C '-0859':10A,13A '-2019':9A,12A,98C,101C 'aka':85C 'allow':34B 'alreadi':41B 'attack':39B 'cisa':55B 'code':43B,50B 'compon':77C 'cve':8A,11A,92C,97C,100C 'driver':29B 'elev':67C,87C 'escal':6A,36B 'exist':71C 'exploit':16B,58B 'fail':78C 'graphic':28B 'handl':81C 'host':21B 'id':93C 'infrastructur':17B 'kernel':27B,52B 'known':63B 'local':38B 'machin':47B 'memori':33B,84C 'microsoft':1A,3A,14A,23B 'mishandl':30B 'mode':53B 'object':31B,82C 'privileg':5A,35B,69C,89C 'proper':80C 'ransomwar':18B,64B 'report':56B 'run':44B,49B 'self':20B 'self-host':19B 'uniqu':95C 'use':65B 'vulner':7A,70C,90C 'wild':61B 'win32k':2A,4A,15A,24B,76C,86C 'window':22B,26B,73C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2019-04-09T21:29:02+00:00","kev":{"dateAdded":"2021-11-03","dueDate":"2022-05-03","requiredAction":"Apply updates per vendor instructions.","knownRansomwareCampaignUse":"Known"},"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2019-0859","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2019-0859","severity":null,"published_at":"2021-11-03T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:53+00:00","fetched_at":"2026-10-25T10:39:08+00:00","note":null},{"source":"epss","external_id":"CVE-2019-0859","url":"https://api.first.org/data/v1/epss?cve=CVE-2019-0859","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:44+00:00","fetched_at":"2026-10-23T19:13:44+00:00","note":null},{"source":"nvd","external_id":"CVE-2019-0859","url":"https://nvd.nist.gov/vuln/detail/CVE-2019-0859","severity":null,"published_at":"2019-04-09T21:29:02+00:00","modified_at":"2026-06-17T02:09:03+00:00","first_seen_at":"2026-10-23T21:57:34+00:00","fetched_at":"2026-10-23T21:57:34+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}