{"cve":"CVE-2021-42340","nvd":{"published":"2021-10-14T20:15:09.060","modified":"2026-06-17T04:09:40.450","status":"Modified","description":"The fix for bug 63362 present in Apache Tomcat 10.1.0-M1 to 10.1.0-M5, 10.0.0-M1 to 10.0.11, 9.0.40 to 9.0.53 and 8.5.60 to 8.5.71 introduced a memory leak. The object introduced to collect metrics for HTTP upgrade connections was not released for WebSocket connections once the connection was closed. This created a memory leak that, over time, could lead to a denial of service via an OutOfMemoryError.","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":["CWE-772"],"references":["https://kc.mcafee.com/corporate/index?page=content&id=SB10379","https://lists.apache.org/thread.html/r8097a2d1550aa78e585fc77e602b9046e6d4099d8d132497c5387784%40%3Ccommits.myfaces.apache.org%3E","https://lists.apache.org/thread.html/r83a35be60f06aca2065f188ee542b9099695d57ced2e70e0885f905c%40%3Cannounce.tomcat.apache.org%3E","https://security.gentoo.org/glsa/202208-34","https://security.netapp.com/advisory/ntap-20211104-0001/"],"products":["apache:tomcat","debian:debian_linux","netapp:hci","netapp:management_services_for_element_software","oracle:agile_engineering_data_management","oracle:big_data_spatial_and_graph","oracle:communications_diameter_signaling_router","oracle:hospitality_cruise_shipboard_property_management_system","oracle:managed_file_transfer","oracle:middleware_common_libraries_and_tools","oracle:payment_interface","oracle:retail_customer_insights","oracle:retail_data_extractor_for_merchandising","oracle:retail_eftlink","oracle:retail_financial_integration","oracle:retail_store_inventory_management","oracle:sd-wan_edge","oracle:taleo_platform"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2021-42340","score":0.11796,"percentile":0.96083,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-wph7-x527-w3h5","url":"https://osv.dev/vulnerability/GHSA-wph7-x527-w3h5","summary":"Missing Release of Resource after Effective Lifetime in Apache Tomcat","modified":"2024-03-11T16:46:20.172045Z","packages":[{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=10.1.0-M1 <10.1.0-M6"],"fixed":["10.1.0-M6"]},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=10.0.0-M1 <10.0.12"],"fixed":["10.0.12"]},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=9.0.40 <9.0.54"],"fixed":["9.0.54"]},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=8.5.60 <8.5.72"],"fixed":["8.5.72"]}]}],"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."]}