CVE-2026-66299

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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."}, {"lang": "es", "value": "Vulnerabilidad de Consumo de Recursos No Controlado en el ejemplo de chat WebSocket de Apache Tomcat.\n\nEste problema afecta a Apache Tomcat: desde 11.0.0-M20 hasta 11.0.24, desde 10.1.24 hasta 10.1.57, desde 9.0.89 hasta 9.0.120. Los usuarios que han seguido la gu\u00eda de seguridad para eliminar la aplicaci\u00f3n web de ejemplos no se ven afectados por este problema.\n\nSe recomienda a los usuarios que eliminen la aplicaci\u00f3n web de ejemplos o que actualicen a la versi\u00f3n 11.0.25, 10.1.58 o 9.0.121 (cuando se publique), que solucionan el problema."}], "id": "CVE-2026-66299", "lastModified": "2026-10-24T13:10:00.147", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 5.3, "baseSeverity": "MEDIUM", "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:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "nvd@nist.gov", "type": "Primary"}, {"cvssData": {"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"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-66299", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-28T17:39:48.240123Z", "version": "2.0.3"}}]}, "published": "2026-07-28T15:17:50.210", "references": [{"source": "security@apache.org", "tags": ["Mailing List", "Vendor Advisory"], "url": "https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Third Party Advisory"], "url": "http://www.openwall.com/lists/oss-security/2026/07/28/25"}], "sourceIdentifier": "security@apache.org", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-400"}], "source": "security@apache.org", "type": "Secondary"}]}

{"bugzilla": {"description": "tomcat: Apache Tomcat: Denial of Service via WebSocket chat example", "id": "2508085", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2508085"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-770", "details": ["A flaw was found in Apache Tomcat. This uncontrolled resource consumption vulnerability, located in the WebSocket chat example, allows a remote attacker to cause a Denial of Service (DoS) by exhausting system resources. This can lead to the affected system becoming unresponsive or crashing."], "mitigation": {"lang": "en:us", "value": "To mitigate this vulnerability, remove the `examples` web application from your Apache Tomcat installation. This can typically be achieved by deleting the `examples` directory or `examples.war` file from the `webapps` directory of your Tomcat installation. A restart of the Tomcat service may be required for the changes to take full effect."}, "name": "CVE-2026-66299", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Under investigation", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Under investigation", "package_name": "tomcat9", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "tomcat6", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Under investigation", "package_name": "pki-servlet-engine", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Under investigation", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Under investigation", "package_name": "tomcat", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "tomcat10", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "tomcat11", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:jboss_enterprise_web_server:5", "fix_state": "Under investigation", "package_name": "jws5-tomcat", "product_name": "Red Hat JBoss Web Server 5"}], "public_date": "2026-07-28T14:29:05Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-66299\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-66299\nhttps://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k"], "statement": "This Moderate severity flaw in Apache Tomcat's WebSocket chat example could lead to a denial of service. The impact is limited as the vulnerable component is part of an example application, which is generally not deployed in production environments. Exploitation requires the example application to be present and accessible.", "threat_severity": "Moderate"}

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