{"id":"CVE-2025-6338","state":"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.","publishedAt":"2025-10-16T09:22:14.709Z","updatedAt":"2026-07-29T08:54:20.124Z","severity":{"score":9.2,"label":"Critical","version":"4.0","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","source":"TQtC"},"assigner":"TQtC","products":["Qt Qt"],"affected":[{"vendor":"Qt","product":"Qt","defaultStatus":"unaffected","versions":[{"version":"0","status":"unaffected","lessThan":"5.15.0","versionType":"python"},{"version":"5.15.0","status":"affected","lessThanOrEqual":"6.8.3","versionType":"python"},{"version":"6.8.4","status":"unaffected","lessThan":"6.9.0","versionType":"python"},{"version":"6.9.0","status":"affected","lessThan":"6.9.2","versionType":"python"}],"platforms":["Windows"]}],"references":["https://codereview.qt-project.org/c/qt/qtbase/+/651495"],"weaknesses":["CWE-459"],"ingestedAt":"2026-10-29T20:10:04.440Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/6xxx/CVE-2025-6338.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-6338","state":"PUBLISHED","datePublished":"2025-10-16T09:22:14.709Z","dateUpdated":"2026-07-29T08:54:20.124Z","assignerShortName":"TQtC","assignerOrgId":"a59d8014-47c4-4630-ab43-e1b13cbe58e3","dateReserved":"2025-06-19T10:25:01.875Z"},"containers":{"cna":{"title":"Possible denial of service with multiple incoming connections to a Schannel based server with a TLS backend","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"Qt","product":"Qt","defaultStatus":"unaffected","versions":[{"version":"0","status":"unaffected","lessThan":"5.15.0","versionType":"python"},{"version":"5.15.0","status":"affected","lessThanOrEqual":"6.8.3","versionType":"python"},{"version":"6.8.4","status":"unaffected","lessThan":"6.9.0","versionType":"python"},{"version":"6.9.0","status":"affected","lessThan":"6.9.2","versionType":"python"}],"platforms":["Windows"]}],"references":[{"url":"https://codereview.qt-project.org/c/qt/qtbase/+/651495"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subAvailabilityImpact":"HIGH","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"CRITICAL","baseScore":9.2,"vectorString":"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"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-459","lang":"en","description":"CWE-459 Incomplete Cleanup","type":"CWE"}]}],"providerMetadata":{"shortName":"TQtC","orgId":"a59d8014-47c4-4630-ab43-e1b13cbe58e3","dateUpdated":"2026-07-29T08:54:20.124Z"},"cpeApplicability":[{"operator":"OR","nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":false,"criteria":"cpe:2.3:a:qt:qt:*:*:windows:*:*:*:*:*","versionStartIncluding":"0","versionEndExcluding":"5.15.0"},{"vulnerable":true,"criteria":"cpe:2.3:a:qt:qt:*:*:windows:*:*:*:*:*","versionStartIncluding":"5.15.0","versionEndIncluding":"6.8.3"},{"vulnerable":false,"criteria":"cpe:2.3:a:qt:qt:*:*:windows:*:*:*:*:*","versionStartIncluding":"6.8.4","versionEndExcluding":"6.9.0"},{"vulnerable":true,"criteria":"cpe:2.3:a:qt:qt:*:*:windows:*:*:*:*:*","versionStartIncluding":"6.9.0","versionEndExcluding":"6.9.2"}]}]}],"source":{"discovery":"INTERNAL"},"x_generator":{"engine":"Vulnogram 0.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2025-10-16T13:14:05.730203Z","id":"CVE-2025-6338","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-16T13:14:11.939Z"}}]}}}