{"id":"CVE-2020-13935","aliases":["BIT-tomcat-2020-13935","GHSA-m7jv-hq7h-mq7c"],"url":"https://o3.security/vulnerability/CVE-2020-13935","summary":"Infinite Loop in Apache Tomcat","details":"The payload length in a WebSocket frame was not correctly validated in Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M1 to 9.0.36, 8.5.0 to 8.5.56 and 7.0.27 to 7.0.104. Invalid payload lengths could trigger an infinite loop. Multiple requests with invalid payload lengths could lead to a denial of service.","published":"2020-07-14T15:15:11.070Z","modified":"2026-10-24T10:30:21.559951632Z","cvss":{"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"},"epss":{"score":0.86608,"percentile":0.99729,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":2,"affectedPackages":[{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","fixedVersion":"10.0.0-M7"},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","fixedVersion":"9.0.37"},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","fixedVersion":"8.5.57"},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","fixedVersion":"7.0.105"},{"ecosystem":"Maven","name":"org.apache.tomcat.embed:tomcat-embed-websocket","fixedVersion":"7.0.105"},{"ecosystem":"Maven","name":"org.apache.tomcat.embed:tomcat-embed-websocket","fixedVersion":"8.5.57"},{"ecosystem":"Maven","name":"org.apache.tomcat.embed:tomcat-embed-websocket","fixedVersion":"9.0.37"},{"ecosystem":"Maven","name":"org.apache.tomcat.embed:tomcat-embed-websocket","fixedVersion":"10.0.0-M7"},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat-websocket","fixedVersion":"10.0.0-M7"},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat-websocket","fixedVersion":"9.0.37"},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat-websocket","fixedVersion":"8.5.57"},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat-websocket","fixedVersion":"7.0.105"}],"fix":{"url":"https://github.com/apache/tomcat/commit/12d715676038efbf9c728af10163f8277fc019d5","label":"apache/tomcat@12d7156"},"references":[{"type":"WEB","url":"https://lists.apache.org/thread.html/r4e5d3c09f4dd2923191e972408b40fb8b42dbff0bc7904d44b651e50%40%3Cusers.tomcat.apache.org%3E"},{"type":"ADVISORY","url":"http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00084.html"},{"type":"ADVISORY","url":"http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00088.html"},{"type":"ADVISORY","url":"https://kc.mcafee.com/corporate/index?page=content&id=SB10332"},{"type":"ADVISORY","url":"https://lists.apache.org/thread.html/rd48c72bd3255bda87564d4da3791517c074d94f8a701f93b85752651%40%3Cannounce.tomcat.apache.org%3E"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2020/07/msg00017.html"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20200724-0003/"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/4448-1/"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/4596-1/"},{"type":"ADVISORY","url":"https://www.debian.org/security/2020/dsa-4727"},{"type":"ADVISORY","url":"https://www.oracle.com/security-alerts/cpuoct2021.html"},{"type":"FIX","url":"https://www.oracle.com//security-alerts/cpujul2021.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpuApr2021.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpuapr2022.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpujan2021.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpujan2022.html"},{"type":"FIX","url":"https://www.oracle.com/security-alerts/cpuoct2020.html"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-13935"},{"type":"WEB","url":"https://github.com/apache/tomcat/commit/12d715676038efbf9c728af10163f8277fc019d5"},{"type":"WEB","url":"https://github.com/apache/tomcat/commit/1c1c77b0efb667cea80b532440b44cea1dc427c3"},{"type":"WEB","url":"https://github.com/apache/tomcat/commit/40fa74c74822711ab878079d0a69f7357926723d"},{"type":"WEB","url":"https://github.com/apache/tomcat/commit/4c04982870d6e730c38e21e58fb653b7cf723784"},{"type":"WEB","url":"https://github.com/apache/tomcat/commit/f9f75c14678b68633f79030ddf4ff827f014cc84"},{"type":"WEB","url":"https://tomcat.apache.org/security-9.html"},{"type":"WEB","url":"https://usn.ubuntu.com/4448-1"},{"type":"WEB","url":"https://usn.ubuntu.com/4596-1"},{"type":"WEB","url":"https://tomcat.apache.org/security-8.html"},{"type":"WEB","url":"https://tomcat.apache.org/security-7.html"},{"type":"WEB","url":"https://tomcat.apache.org/security-10.html"},{"type":"WEB","url":"https://security.netapp.com/advisory/ntap-20200724-0003"},{"type":"WEB","url":"https://lists.apache.org/thread.html/r4e5d3c09f4dd2923191e972408b40fb8b42dbff0bc7904d44b651e50@%3Cusers.tomcat.apache.org%3E"},{"type":"PACKAGE","url":"https://github.com/apache/tomcat"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-24T10:30:21.559951632Z"}}