{"id":"CVE-2026-97790","aliases":["EUVD-2026-100310","GHSA-hg3m-hc8g-63v7"],"status":"published","title":"Windows Container Isolation FS Filter Driver (unionfs.sys) Tampering Vulnerability","description":"Improper link resolution before file access ('link following') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to perform tampering locally.","severity":{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00385,"percentile":0.33028,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-59"],"published":"2026-10-13T19:01:29Z","modified":"2026-11-10T20:45:42Z","products":[{"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_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-2026-97790","tags":["vendor-advisory","patch","Patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97790"},{"url":"https://github.com/advisories/GHSA-hg3m-hc8g-63v7"}],"sources":{"cve":[{"id":"CVE-2026-97790","title":"Windows Container Isolation FS Filter Driver (unionfs.sys) Tampering Vulnerability","description":"Improper link resolution before file access ('link following') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T19:01:29.693Z","modified":"2026-11-10T20:45:42.266Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C","level":"medium","assessor":"cna"}],"cwes":["CWE-59"],"updated_at":"2026-11-10T22:18:30.298108Z"}],"euvd":[{"id":"EUVD-2026-100310","description":"Improper link resolution before file access ('link following') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T19:01:29Z","modified":"2026-11-10T20:45:42Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C","level":"medium"}],"updated_at":"2026-11-10T22:23:55.776344Z"}],"ghsa":[{"id":"GHSA-hg3m-hc8g-63v7","title":"Improper link resolution before file access ('link following') in Windows Container Isolation FS...","description":"Improper link resolution before file access ('link following') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T21:37:14Z","modified":"2026-10-13T21:37:15Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"cwes":["CWE-59"],"updated_at":"2026-11-02T15:13:20.228797Z"}],"nvd":[{"id":"CVE-2026-97790","description":"Improper link resolution before file access ('link following') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T19:22:17.097Z","modified":"2026-10-16T10:40:56.477Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-59"],"updated_at":"2026-11-02T14:12:58.630796Z"}]}}