{"id":"CVE-2026-97787","aliases":["EUVD-2026-100309","GHSA-6x7p-x5cg-8hh8"],"status":"published","title":"Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability","description":"Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.","severity":{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00214,"percentile":0.11883,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-362"],"published":"2026-10-13T19:01:29Z","modified":"2026-11-10T20:45:41Z","products":[{"vendor":"microsoft","product":"windows 11 version 23h2"},{"vendor":"microsoft","product":"windows 11 version 24h2"},{"vendor":"microsoft","product":"windows 11 version 25h2"},{"vendor":"microsoft","product":"windows 11 version 26h1"},{"vendor":"microsoft","product":"windows 11 version 26h2"},{"vendor":"microsoft","product":"windows server 2022"},{"vendor":"microsoft","product":"windows server 2025"},{"vendor":"microsoft","product":"windows server 2025 (server core installation)"},{"vendor":"microsoft","product":"windows_11_23h2"},{"vendor":"microsoft","product":"windows_11_24h2"},{"vendor":"microsoft","product":"windows_11_25h2"},{"vendor":"microsoft","product":"windows_11_26h1"},{"vendor":"microsoft","product":"windows_11_26h2"},{"vendor":"microsoft","product":"windows_server_2022"},{"vendor":"microsoft","product":"windows_server_2025"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-97787","tags":["vendor-advisory","patch","Patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97787"},{"url":"https://github.com/advisories/GHSA-6x7p-x5cg-8hh8"}],"sources":{"cve":[{"id":"CVE-2026-97787","title":"Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability","description":"Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T19:01:29.628Z","modified":"2026-11-10T20:45:41.764Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna"}],"cwes":["CWE-362"],"updated_at":"2026-11-10T22:18:30.298108Z"}],"euvd":[{"id":"EUVD-2026-100309","description":"Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T19:01:29Z","modified":"2026-11-10T20:45:41Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high"}],"updated_at":"2026-11-10T22:23:55.776344Z"}],"ghsa":[{"id":"GHSA-6x7p-x5cg-8hh8","title":"Concurrent execution using shared resource with improper synchronization ('race condition') in...","description":"Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T21:37:14Z","modified":"2026-10-13T21:37:19Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-362"],"updated_at":"2026-11-02T15:13:20.971444Z"}],"nvd":[{"id":"CVE-2026-97787","description":"Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T19:22:16.563Z","modified":"2026-10-16T10:41:01.4Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-362"],"updated_at":"2026-11-02T14:12:58.630796Z"}]}}