{"id":"CVE-2026-40377","aliases":["EUVD-2026-29654","GHSA-m8m3-jvh9-rpcr"],"status":"published","title":"Microsoft Cryptographic Services Elevation of Privilege Vulnerability","description":"Heap-based buffer overflow in Windows Cryptographic Services allows an authorized attacker to elevate privileges locally.","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:U/RL:O/RC:C","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00304,"percentile":0.23404,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-122"],"published":"2026-05-12T16:58:40Z","modified":"2026-08-10T15:12:52Z","products":[{"vendor":"microsoft","product":"windows 10 version 1607"},{"vendor":"microsoft","product":"windows 10 version 1809"},{"vendor":"microsoft","product":"windows 10 version 21h2"},{"vendor":"microsoft","product":"windows 10 version 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Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40377"},{"url":"https://github.com/advisories/GHSA-m8m3-jvh9-rpcr"}],"sources":{"cve":[{"id":"CVE-2026-40377","title":"Microsoft Cryptographic Services Elevation of Privilege Vulnerability","description":"Heap-based buffer overflow in Windows Cryptographic Services allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-05-12T16:58:40.526Z","modified":"2026-08-10T15:12:52.509Z","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:U/RL:O/RC:C","level":"high","assessor":"cna"}],"cwes":["CWE-122"],"updated_at":"2026-11-02T13:43:11.445168Z"}],"euvd":[{"id":"EUVD-2026-29654","description":"Heap-based buffer overflow in Windows Cryptographic Services allows an authorized attacker to elevate privileges 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