{"id":"CVE-2026-96218","aliases":["EUVD-2026-99747","GHSA-q5gp-6748-vfmw"],"status":"published","title":"Windows Update Stack Tampering Vulnerability","description":"Improper access control in Windows Update Stack 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":"2026-11-09","score":0.00552,"percentile":0.46425,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-15"],"published":"2026-10-13T19:00:31Z","modified":"2026-10-31T18:06:47Z","products":[{"vendor":"microsoft","product":"windows 10 version 1809"},{"vendor":"microsoft","product":"windows 10 version 21h2"},{"vendor":"microsoft","product":"windows 10 version 22h2"},{"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 2019"},{"vendor":"microsoft","product":"windows server 2019 (server core installation)"},{"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_10_1809"},{"vendor":"microsoft","product":"windows_10_21h2"},{"vendor":"microsoft","product":"windows_10_22h2"},{"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_2019"},{"vendor":"microsoft","product":"windows_server_2022"},{"vendor":"microsoft","product":"windows_server_2025"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96218","tags":["vendor-advisory","patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-96218"},{"url":"https://github.com/advisories/GHSA-q5gp-6748-vfmw"}],"sources":{"cve":[{"id":"CVE-2026-96218","title":"Windows Update Stack Tampering Vulnerability","description":"Improper access control in Windows Update Stack allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T19:00:31.55Z","modified":"2026-10-31T18:06:47.846Z","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-15"],"updated_at":"2026-11-02T14:20:00.511569Z"}],"euvd":[{"id":"EUVD-2026-99747","description":"Improper access control in Windows Update Stack allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T19:00:31Z","modified":"2026-10-31T18:06:47Z","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":"2026-11-02T16:58:53.436601Z"}],"ghsa":[{"id":"GHSA-q5gp-6748-vfmw","title":"Improper access control in Windows Update Stack allows an authorized attacker to perform...","description":"Improper access control in Windows Update Stack allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T21:36:57Z","modified":"2026-10-13T21:37:02Z","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-15"],"updated_at":"2026-11-02T15:13:19.647865Z"}],"nvd":[{"id":"CVE-2026-96218","description":"Improper access control in Windows Update Stack allows an authorized attacker to perform tampering locally.","status":"published","published":"2026-10-13T19:21:47.59Z","modified":"2026-10-16T16:22:45.983Z","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-15"],"updated_at":"2026-11-02T14:12:58.13117Z"}]}}