{"id":"CVE-2026-66804","published":"2026-08-11T17:05:36Z","modified":"2026-10-21T20:53:06Z","title":"Microsoft Windows Cross Device Service Elevation of Privilege Vulnerability","vendor":"Microsoft","product":"Windows 10 Version 22H2","tier":"tail","description":{"text":"Improper access control in Windows Cross Device Service allows an authorized attacker to elevate privileges locally.","provenance":"source","from":"CVE.org"},"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/E:U/RL:O/RC:C","provenance":"source","from":"CVE.org CNA"},"epss":{"score":0.00298,"percentile":0.22414,"provenance":"source"},"cwes":[{"id":"CWE-284","name":"Improper Access Control"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66804","tags":["vendor-advisory","patch"]}],"priority":{"score":14.9,"factors":[{"name":"EPSS percentile","points":4.48},{"name":"Public exploit code","points":5.0},{"name":"CVSS severity","points":5.46}]},"exploitSources":{"pocGithub":{"count":4,"skipped":0,"earliest":"2026-07-19","earliestUrl":"https://github.com/ZeroDayVPN/CVE-2026-66804-CrossDevice-Service-EoP","repos":[{"name":"Rat5ak/CVE-2026-66804-CrossDevice-Service-EoP","url":"https://github.com/Rat5ak/CVE-2026-66804-CrossDevice-Service-EoP","stars":25,"created":"2026-08-13"},{"name":"DavidCarliez/CVE-2026-66804-CrossDevice-LPE","url":"https://github.com/DavidCarliez/CVE-2026-66804-CrossDevice-LPE","stars":16,"created":"2026-07-23"},{"name":"ZeroDayVPN/CVE-2026-66804-CrossDevice-Service-EoP","url":"https://github.com/ZeroDayVPN/CVE-2026-66804-CrossDevice-Service-EoP","stars":2,"created":"2026-07-19"},{"name":"CypherHippie/CVE-2026-66804","url":"https://github.com/CypherHippie/CVE-2026-66804","stars":1,"created":"2026-07-25"}]},"first":{"date":"2026-07-19","source":"PoC-in-GitHub","url":"https://github.com/ZeroDayVPN/CVE-2026-66804-CrossDevice-Service-EoP"},"provenance":"source"},"vendorSlug":"microsoft","affectedVersions":[{"vendor":"Microsoft","product":"Windows 10 Version 22H2","versions":[">= 10.0.19045.0, < 10.0.19045.7663"]},{"vendor":"Microsoft","product":"Windows 11 Version 24H2","versions":[">= 10.0.26100.0, < 10.0.26100.9168"]},{"vendor":"Microsoft","product":"Windows 11 Version 25H2","versions":[">= 10.0.26200.0, < 10.0.26200.9168"]},{"vendor":"Microsoft","product":"Windows 11 version 26H1","versions":[">= 10.0.28000.0, < 10.0.28000.2704"]}],"euvd":{"id":"EUVD-2026-56595","exploited":false,"provenance":"source"},"lineage":{"familyId":"fam-class-microsoft-windows-cwe-284"}}