{"id":"CVE-2020-11996","revision":null,"records":[{"revision":"73001f5aef094b2cadaf590797827b08","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2020-11996","aliases":[],"title":"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 conc…","description":"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.","state":0,"publishedAt":"2020-06-26T16:27:20+00:00","modifiedAt":"2026-10-08T21:13:56.997+00:00","affected":[{"ecosystem":"Vendor product","name":"Apache Tomcat","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Apache Tomcat\",\n                    \"vendor\": \"Apache\",\n                    \"versions\": [\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"10.0.0-M1 to 10.0.0-M5\"\n                        },\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"9.0.0.M1 to 9.0.35\"\n                        },\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"8.5.0 to 8.5.55\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://lists.apache.org/thread.html/r5541ef6b6b68b49f76fc4c45695940116da2bcbe0312ef204a00a2e0%40%3Cannounce.tomcat.apache.org%3E","https://lists.apache.org/thread.html/ra7092f7492569b39b04ec0decf52628ba86c51f15efb38f5853e2760%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/rb4ee49ecc4c59620ffd5e66e84a17e526c2c3cfa95d0cd682d90d338%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/rb820f1a2a02bf07414be12c653c2ab5321fd87b9bf6c5e635c53ff4b%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r8f7484589454638af527182ae55ef5b628ba00c05c5b11887c922fb1%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r74f5a8204efe574cbfcd95b2a16236fe95beb45c4d9fee3dc789dca9%40%3Ccommits.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/rea65d6ef2e45dd1c45faae83922042732866c7b88fa109b76c83db52%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/rc80b96b4b96618b2b7461cb90664a428cfd6605eea9f74e51b792542%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r93ca628ef3a4530dfe5ac49fddc795f0920a4b2a408b57a30926a42b%40%3Ccommits.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r8f3d416c193bc9384a8a7dd368623d441f5fcaff1057115008100561%40%3Ccommits.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r9ad911fe49450ed9405827af0e7a74104041081ff91864b1f2546bbd%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/ref0339792ac6dac1dba83c071a727ad72380899bde60f6aaad4031b9%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r6c29801370a36c1a5159679269777ad0c73276d3015b8bbefea66e5c%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r3ea96d8f36dd404acce83df8aeb22a9e807d6c13ca9c5dec72f872cd%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.debian.org/debian-lts-announce/2020/07/msg00010.html","https://www.debian.org/security/2020/dsa-4727","http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00064.html","http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00072.html","https://lists.apache.org/thread.html/r2529016c311ce9485e6f173446d469600fdfbb94dccadfcd9dfdac79%40%3Cusers.tomcat.apache.org%3E","https://www.oracle.com/security-alerts/cpuoct2020.html","https://security.netapp.com/advisory/ntap-20200709-0002/","https://usn.ubuntu.com/4596-1/","https://www.oracle.com/security-alerts/cpujan2021.html","https://lists.apache.org/thread.html/r5a4f80a6acc6607d61dae424b643b594c6188dd4e1eff04705c10db2%40%3Cnotifications.ofbiz.apache.org%3E"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2020-11996","license":"CVE Program Terms of Use","key":"cve-program:CVE-2020-11996","identifiers":["CVE-2020-11996"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. 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