{"cve":"CVE-2020-11996","nvd":{"published":"2020-06-26T17:15:10.153","modified":"2026-10-08T22:16:56.027","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":[],"references":["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://lists.apache.org/thread.html/r3ea96d8f36dd404acce83df8aeb22a9e807d6c13ca9c5dec72f872cd%40%3Cnotifications.ofbiz.apache.org%3E","https://lists.apache.org/thread.html/r5541ef6b6b68b49f76fc4c45695940116da2bcbe0312ef204a00a2e0%40%3Cannounce.tomcat.apache.org%3E"],"products":["apache:tomcat","canonical:ubuntu_linux","debian:debian_linux","netapp:oncommand_system_manager","opensuse:leap","oracle:mysql_enterprise_monitor","oracle:siebel_ui_framework","oracle:workload_manager"],"source":"nvd","synced_at":"2026-10-19T21:06:22.076270124+00:00"},"epss":{"cve":"CVE-2020-11996","score":0.26699,"percentile":0.98011,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-53hp-jpwq-2jgq","url":"https://osv.dev/vulnerability/GHSA-53hp-jpwq-2jgq","summary":"Uncontrolled Resource Consumption in Apache Tomcat","modified":"2026-06-11T14:45:08.723638939Z","packages":[{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=10.0.0-M1 <10.0.0-M5"],"fixed":["10.0.0-M5"]},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=9.0.0.M1 <9.0.35"],"fixed":["9.0.35"]},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=8.5.0 <8.5.55"],"fixed":["8.5.55"]},{"ecosystem":"Maven","name":"org.apache.tomcat.embed:tomcat-embed-core","purl":"pkg:maven/org.apache.tomcat.embed/tomcat-embed-core","ranges":[">=10.0.0-M1 <10.0.0-M5"],"fixed":["10.0.0-M5"]},{"ecosystem":"Maven","name":"org.apache.tomcat.embed:tomcat-embed-core","purl":"pkg:maven/org.apache.tomcat.embed/tomcat-embed-core","ranges":[">=9.0.0.M1 <9.0.35"],"fixed":["9.0.35"]},{"ecosystem":"Maven","name":"org.apache.tomcat.embed:tomcat-embed-core","purl":"pkg:maven/org.apache.tomcat.embed/tomcat-embed-core","ranges":[">=8.5.0 <8.5.55"],"fixed":["8.5.55"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}