{"api_version":"1","generated_at":"2026-08-01T16:38:52+00:00","cve":"CVE-2026-66299","urls":{"html":"https://cve.report/CVE-2026-66299","api":"https://cve.report/api/cve/CVE-2026-66299.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-66299","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-66299"},"summary":{"title":"Apache Tomcat: DoS via WebSocket chat example","description":"Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example.\n\nThis issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue.\n\nUsers are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.","state":"PUBLISHED","assigner":"apache","published_at":"2026-07-28 15:17:50","updated_at":"2026-07-28 18:17:23"},"problem_types":["CWE-400","CWE-400 CWE-400 Uncontrolled Resource Consumption"],"metrics":[{"version":"3.1","source":"ADP","type":"DECLARED","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}},{"version":"3.1","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"references":[{"url":"https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k","name":"https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k","refsource":"security@apache.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"http://www.openwall.com/lists/oss-security/2026/07/28/25","name":"http://www.openwall.com/lists/oss-security/2026/07/28/25","refsource":"af854a3a-2127-422b-91ae-364da2661108","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-66299","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66299","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Apache Software Foundation","product":"Apache Tomcat","version":"affected 11.0.0-M20 11.0.24 semver","platforms":[]},{"source":"CNA","vendor":"Apache Software Foundation","product":"Apache Tomcat","version":"affected 10.1.24 10.1.57 semver","platforms":[]},{"source":"CNA","vendor":"Apache Software Foundation","product":"Apache Tomcat","version":"affected 9.0.89 9.0.120 semver","platforms":[]},{"source":"CNA","vendor":"Apache Software Foundation","product":"Apache Tomcat","version":"unaffected 8.5.100 semver","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"4ra1n, pyn3rd and unam4","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"66299","cve":"CVE-2026-66299","epss":"0.003100000","percentile":"0.233860000","score_date":"2026-07-29","updated_at":"2026-07-30 00:09:13"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"providerMetadata":{"dateUpdated":"2026-07-28T17:31:30.996Z","orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE"},"references":[{"url":"http://www.openwall.com/lists/oss-security/2026/07/28/25"}],"title":"CVE Program Container"},{"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}},{"other":{"content":{"id":"CVE-2026-66299","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-07-28T17:39:48.240123Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-07-28T17:40:03.853Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"Apache Tomcat","vendor":"Apache Software Foundation","versions":[{"lessThanOrEqual":"11.0.24","status":"affected","version":"11.0.0-M20","versionType":"semver"},{"lessThanOrEqual":"10.1.57","status":"affected","version":"10.1.24","versionType":"semver"},{"lessThanOrEqual":"9.0.120","status":"affected","version":"9.0.89","versionType":"semver"},{"lessThanOrEqual":"8.5.100","status":"unaffected","version":"0","versionType":"semver"}]}],"credits":[{"lang":"en","type":"finder","value":"4ra1n, pyn3rd and unam4"}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<p>Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example.</p><p>This issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue.</p><p>Users are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.</p>"}],"value":"Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example.\n\nThis issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue.\n\nUsers are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue."}],"metrics":[{"other":{"content":{"text":"low"},"type":"Textual description of severity"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","description":"CWE-400 Uncontrolled Resource Consumption","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-07-28T14:29:05.810Z","orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","shortName":"apache"},"references":[{"tags":["vendor-advisory"],"url":"https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k"}],"source":{"discovery":"EXTERNAL"},"title":"Apache Tomcat: DoS via WebSocket chat example","x_generator":{"engine":"Vulnogram 0.2.0"}}},"cveMetadata":{"assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","assignerShortName":"apache","cveId":"CVE-2026-66299","datePublished":"2026-07-28T14:29:05.810Z","dateReserved":"2026-07-24T14:53:11.561Z","dateUpdated":"2026-07-28T17:40:03.853Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-28 15:17:50","lastModifiedDate":"2026-07-28 18:17:23","problem_types":["CWE-400","CWE-400 CWE-400 Uncontrolled Resource Consumption"],"metrics":{"cvssMetricV31":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-28T17:39:48.240123Z","id":"CVE-2026-66299","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"66299","Ordinal":"1","Title":"Apache Tomcat: DoS via WebSocket chat example","CVE":"CVE-2026-66299","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"66299","Ordinal":"1","NoteData":"Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example.\n\nThis issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue.\n\nUsers are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.","Type":"Description","Title":"Apache Tomcat: DoS via WebSocket chat example"}]}}}