{"id":"CVE-2021-31956","aliases":["EUVD-2021-18829","GHSA-jj4q-6c47-cggx"],"status":"published","title":"Windows NTFS Elevation of Privilege Vulnerability","description":"Windows NTFS Elevation of Privilege Vulnerability","severity":{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.22273,"percentile":0.97713,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":true,"fix_available":false},"cwes":["CWE-191","CWE-269","CWE-787"],"published":"2021-06-08T22:46:25Z","modified":"2026-06-17T03:52:33Z","kev":{"date_added":"2021-11-03","due_date":"2021-11-17","required_action":"Apply updates per vendor instructions.","known_ransomware_use":"Unknown"},"exploitation":[{"source":"euvd","since":"2021-11-03"},{"source":"kev","since":"2021-11-03"}],"exploits":[{"source":"pocgithub","id":"hzshang/CVE-2021-31956","title":"hzshang/CVE-2021-31956","date":"2021-11-22","url":"https://github.com/hzshang/CVE-2021-31956"},{"source":"pocgithub","id":"aazhuliang/CVE-2021-31956-EXP","title":"aazhuliang/CVE-2021-31956-EXP","date":"2022-01-11","url":"https://github.com/aazhuliang/CVE-2021-31956-EXP"},{"source":"pocgithub","id":"Y3A/CVE-2021-31956","title":"Y3A/CVE-2021-31956","date":"2022-09-02","url":"https://github.com/Y3A/CVE-2021-31956"},{"source":"pocgithub","id":"hoangprod/CVE-2021-31956-POC","title":"hoangprod/CVE-2021-31956-POC","date":"2023-06-05","url":"https://github.com/hoangprod/CVE-2021-31956-POC"},{"source":"pocgithub","id":"DaoshuReal/UAC-Elevation-CVE","title":"DaoshuReal/UAC-Elevation-CVE","date":"2025-05-07","url":"https://github.com/DaoshuReal/UAC-Elevation-CVE"},{"source":"pocgithub","id":"deletehead/Pool-Overflow-CVE-2021-31956","title":"deletehead/Pool-Overflow-CVE-2021-31956","date":"2025-06-17","url":"https://github.com/deletehead/Pool-Overflow-CVE-2021-31956"}],"products":[{"vendor":"microsoft","product":"windows"},{"vendor":"microsoft","product":"windows 10 version 1507"},{"vendor":"microsoft","product":"windows 10 version 1607"},{"vendor":"microsoft","product":"windows 10 version 1809"},{"vendor":"microsoft","product":"windows 10 version 1909"},{"vendor":"microsoft","product":"windows 10 version 2004"},{"vendor":"microsoft","product":"windows 10 version 20h2"},{"vendor":"microsoft","product":"windows 10 version 21h1"},{"vendor":"microsoft","product":"windows 7"},{"vendor":"microsoft","product":"windows 7 service pack 1"},{"vendor":"microsoft","product":"windows 8.1"},{"vendor":"microsoft","product":"windows server 2008  service pack 2"},{"vendor":"microsoft","product":"windows server 2008 r2 service pack 1"},{"vendor":"microsoft","product":"windows server 2008 r2 service pack 1 (server core installation)"},{"vendor":"microsoft","product":"windows server 2008 service pack 2"},{"vendor":"microsoft","product":"windows server 2008 service pack 2 (server core installation)"},{"vendor":"microsoft","product":"windows server 2012"},{"vendor":"microsoft","product":"windows server 2012 (server core installation)"},{"vendor":"microsoft","product":"windows server 2012 r2"},{"vendor":"microsoft","product":"windows server 2012 r2 (server core installation)"},{"vendor":"microsoft","product":"windows server 2016"},{"vendor":"microsoft","product":"windows server 2016 (server core installation)"},{"vendor":"microsoft","product":"windows server 2019"},{"vendor":"microsoft","product":"windows server 2019 (server core installation)"},{"vendor":"microsoft","product":"windows server version 2004"},{"vendor":"microsoft","product":"windows server version 20h2"},{"vendor":"microsoft","product":"windows_10_1507"},{"vendor":"microsoft","product":"windows_10_1607"},{"vendor":"microsoft","product":"windows_10_1809"},{"vendor":"microsoft","product":"windows_10_1909"},{"vendor":"microsoft","product":"windows_10_2004"},{"vendor":"microsoft","product":"windows_10_20h2"},{"vendor":"microsoft","product":"windows_10_21h1"},{"vendor":"microsoft","product":"windows_7"},{"vendor":"microsoft","product":"windows_8.1"},{"vendor":"microsoft","product":"windows_rt_8.1"},{"vendor":"microsoft","product":"windows_server_2004"},{"vendor":"microsoft","product":"windows_server_2008"},{"vendor":"microsoft","product":"windows_server_2012"},{"vendor":"microsoft","product":"windows_server_2016"},{"vendor":"microsoft","product":"windows_server_2019"},{"vendor":"microsoft","product":"windows_server_20h2"}],"references":[{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31956","tags":["x_refsource_MISC","x_transferred","Patch","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31956","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-31956"},{"url":"https://github.com/advisories/GHSA-jj4q-6c47-cggx"}],"sources":{"cve":[{"id":"CVE-2021-31956","title":"Windows NTFS Elevation of Privilege Vulnerability","description":"Windows NTFS Elevation of Privilege Vulnerability","status":"published","published":"2021-06-08T22:46:25Z","modified":"2026-01-12T20:27:21.01Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C","level":"high","assessor":"cna"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:33:05.331617Z"}],"euvd":[{"id":"EUVD-2021-18829","description":"Windows NTFS Elevation of Privilege Vulnerability","status":"published","published":"2021-06-08T22:46:25Z","modified":"2026-01-12T20:27:21Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C","level":"high"}],"exploited_since":"2021-11-03","updated_at":"2026-11-02T19:48:53.22038Z"}],"ghsa":[{"id":"GHSA-jj4q-6c47-cggx","title":"Windows NTFS Elevation of Privilege Vulnerability","description":"Windows NTFS Elevation of Privilege Vulnerability","status":"published","published":"2022-05-24T19:04:48Z","modified":"2025-10-22T00:32:13Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-191","CWE-269"],"updated_at":"2026-11-02T15:04:04.786232Z"}],"kev":[{"id":"CVE-2021-31956","title":"Microsoft Windows NTFS Privilege Escalation Vulnerability","description":"Microsoft Windows New Technology File System (NTFS) contains an unspecified vulnerability that allows attackers to escalate privileges via a specially crafted application.","cwes":["CWE-191","CWE-787"],"kev":{"date_added":"2021-11-03","due_date":"2021-11-17","required_action":"Apply updates per vendor instructions.","known_ransomware_use":"Unknown"},"updated_at":"2026-11-02T17:00:17.050017Z"}],"nvd":[{"id":"CVE-2021-31956","description":"Windows NTFS Elevation of Privilege Vulnerability","status":"published","published":"2021-06-08T23:15:08.847Z","modified":"2026-06-17T03:52:33.957Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"2.0","score":9.3,"vector":"AV:N/AC:M/Au:N/C:C/I:C/A:C","level":"high","assessor":"primary"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:06:54.439974Z"}]}}