{"schema_version":"1.7.5","id":"CVE-2020-11996","published":"2020-06-26T17:15:10.153Z","modified":"2026-07-08T05:55:40.733332589Z","aliases":["BIT-tomcat-2020-11996","GHSA-53hp-jpwq-2jgq"],"related":["SUSE-SU-2020:1841-1","SUSE-SU-2020:1962-1","SUSE-SU-2020:1963-1","SUSE-SU-2020:1983-1","openSUSE-SU-2020:1051-1","openSUSE-SU-2020:1063-1","openSUSE-SU-2024:11468-1","openSUSE-SU-2024:13441-1"],"details":"A specially crafted sequence of HTTP/2 requests sent to Apache Tomcat 10.0.0-M1 to 10.0.0-M5, 9.0.0.M1 to 9.0.35 and 8.5.0 to 8.5.55 could trigger high CPU usage for several seconds. If a sufficient number of such requests were made on concurrent HTTP/2 connections, the server could become unresponsive.","affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/apache/tomcat","events":[{"introduced":"e37b977db6f47e4380ad67114a49e8568951c953"},{"last_affected":"c8a57e4a2db8e5af314bae48123fb5990da5b7a5"},{"introduced":"16bf392c67833ad549733b58c350ff92b5ee782a"},{"last_affected":"fc2c65d390444d75412855ad0de8b878018d02dc"},{"introduced":"29b07def810d335012e738b22ab44d4e232b50d1"},{"last_affected":"b3a208c6d6d01c553178c5e718e750b0eb318151"}],"database_specific":{"cpe":["cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone1:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone10:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone11:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone12:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone13:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone14:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone15:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone16:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone17:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone18:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone19:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone2:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone20:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone21:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone22:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone23:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone24:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone25:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone26:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone27:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone3:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone4:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone5:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone6:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone7:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone8:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:9.0.0:milestone9:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:10.0.0:milestone1:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:10.0.0:milestone2:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:10.0.0:milestone3:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:10.0.0:milestone4:*:*:*:*:*:*","cpe:2.3:a:apache:tomcat:10.0.0:milestone5:*:*:*:*:*:*"],"extracted_events":[{"introduced":"8.5.0"},{"last_affected":"8.5.55"},{"introduced":"9.0.0"},{"last_affected":"9.0.35"},{"introduced":"9.0.0-milestone1"},{"last_affected":"9.0.0-milestone1"},{"introduced":"9.0.0-milestone10"},{"last_affected":"9.0.0-milestone10"},{"introduced":"9.0.0-milestone11"},{"last_affected":"9.0.0-milestone11"},{"introduced":"9.0.0-milestone12"},{"last_affected":"9.0.0-milestone12"},{"introduced":"9.0.0-milestone13"},{"last_affected":"9.0.0-milestone13"},{"introduced":"9.0.0-milestone14"},{"last_affected":"9.0.0-milestone14"},{"introduced":"9.0.0-milestone15"},{"last_affected":"9.0.0-milestone15"},{"introduced":"9.0.0-milestone16"},{"last_affected":"9.0.0-milestone16"},{"introduced":"9.0.0-milestone17"},{"last_affected":"9.0.0-milestone17"},{"introduced":"9.0.0-milestone18"},{"last_affected":"9.0.0-milestone18"},{"introduced":"9.0.0-milestone19"},{"last_affected":"9.0.0-milestone19"},{"introduced":"9.0.0-milestone2"},{"last_affected":"9.0.0-milestone2"},{"introduced":"9.0.0-milestone20"},{"last_affected":"9.0.0-milestone20"},{"introduced":"9.0.0-milestone21"},{"last_affected":"9.0.0-milestone21"},{"introduced":"9.0.0-milestone22"},{"last_affected":"9.0.0-milestone22"},{"introduced":"9.0.0-milestone23"},{"last_affected":"9.0.0-milestone23"},{"introduced":"9.0.0-milestone24"},{"last_affected":"9.0.0-milestone24"},{"introduced":"9.0.0-milestone25"},{"last_affected":"9.0.0-milestone25"},{"introduced":"9.0.0-milestone26"},{"last_affected":"9.0.0-milestone26"},{"introduced":"9.0.0-milestone27"},{"last_affected":"9.0.0-milestone27"},{"introduced":"9.0.0-milestone3"},{"last_affected":"9.0.0-milestone3"},{"introduced":"9.0.0-milestone4"},{"last_affected":"9.0.0-milestone4"},{"introduced":"9.0.0-milestone5"},{"last_affected":"9.0.0-milestone5"},{"introduced":"9.0.0-milestone6"},{"last_affected":"9.0.0-milestone6"},{"introduced":"9.0.0-milestone7"},{"last_affected":"9.0.0-milestone7"},{"introduced":"9.0.0-milestone8"},{"last_affected":"9.0.0-milestone8"},{"introduced":"9.0.0-milestone9"},{"last_affected":"9.0.0-milestone9"},{"introduced":"10.0.0-milestone1"},{"last_affected":"10.0.0-milestone1"},{"introduced":"10.0.0-milestone2"},{"last_affected":"10.0.0-milestone2"},{"introduced":"10.0.0-milestone3"},{"last_affected":"10.0.0-milestone3"},{"introduced":"10.0.0-milestone4"},{"last_affected":"10.0.0-milestone4"},{"introduced":"10.0.0-milestone5"},{"last_affected":"10.0.0-milestone5"}],"source":["CPE_RANGE","CPE_STRING"]}}],"versions":["10.0.0-milestone1","10.0.0-milestone2","10.0.0-milestone3","10.0.0-milestone4","10.0.0-milestone5","9.0.0-milestone1","9.0.0-milestone10","9.0.0-milestone11","9.0.0-milestone12","9.0.0-mileston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