{"id":"CVE-2025-6338","aliases":["EUVD-2025-34743","GHSA-m4hj-jpxf-jhjp"],"status":"published","title":"Possible denial of service with multiple incoming connections to a Schannel based server with a TLS backend","description":"There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which can lead to a Denial of Service over a long period.\n\nThis issue affects Qt from 5.15.0 through 6.8.3, from 6.9.0 before 6.9.2.","severity":{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00427,"percentile":0.37373,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-459"],"published":"2025-10-16T09:22:14Z","modified":"2026-10-09T10:10:00Z","products":[{"vendor":"qt","product":"qt"},{"vendor":"the qt company","product":"qt"}],"references":[{"url":"https://codereview.qt-project.org/c/qt/qtbase/+/651495"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-6338"},{"url":"https://github.com/advisories/GHSA-m4hj-jpxf-jhjp"}],"sources":{"cve":[{"id":"CVE-2025-6338","title":"Possible denial of service with multiple incoming connections to a Schannel based server with a TLS backend","description":"There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which can lead to a Denial of Service over a long period.\n\nThis issue affects Qt from 5.15.0 through 6.8.3, from 6.9.0 before 6.9.2.","status":"published","published":"2025-10-16T09:22:14.709Z","modified":"2026-07-29T08:54:20.124Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H","level":"critical","assessor":"cna"}],"cwes":["CWE-459"],"updated_at":"2026-11-02T14:32:40.072186Z"}],"euvd":[{"id":"EUVD-2025-34743","description":"There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which can lead to a Denial of Service over a long period.\n\nThis issue affects Qt from 5.15.0 through 6.8.3, from 6.9.0 before 6.9.2.","status":"published","published":"2025-10-16T09:22:14Z","modified":"2026-07-29T08:54:20Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H","level":"critical"}],"updated_at":"2026-11-02T18:02:30.59681Z"}],"ghsa":[{"id":"GHSA-m4hj-jpxf-jhjp","title":"There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which...","description":"There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which can lead to a Denial of Service over a long period.This issue affects Qt from 5.15.0 through 6.8.3, from 6.9.0 before 6.9.2.","status":"published","published":"2025-10-16T12:30:23Z","modified":"2025-10-16T12:30:27Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical"}],"cwes":["CWE-459"],"updated_at":"2026-11-02T15:04:00.621717Z"}],"nvd":[{"id":"CVE-2025-6338","description":"There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which can lead to a Denial of Service over a long period.\n\nThis issue affects Qt from 5.15.0 through 6.8.3, from 6.9.0 before 6.9.2.","status":"published","published":"2025-10-16T10:15:44.51Z","modified":"2026-10-09T10:10:00.193Z","cvss":[{"version":"4.0","score":9.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"critical","assessor":"secondary"}],"cwes":["CWE-459"],"updated_at":"2026-11-02T14:11:38.17237Z"}]}}