{"id":"CVE-2021-34431","details":"In Eclipse Mosquitto version 1.6 to 2.0.10, if an authenticated client that had connected with MQTT v5 sent a crafted CONNECT message to the broker a memory leak would occur, which could be used to provide a DoS attack against the broker.","modified":"2026-03-14T08:43:09.569846Z","published":"2021-07-22T14:15:08.050Z","references":[{"type":"ADVISORY","url":"https://bugs.eclipse.org/bugs/show_bug.cgi?id=573191"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/eclipse/mosquitto","events":[{"introduced":"4555ee79e513d9a6dc5c13d527c56cb2cfdd24d0"},{"last_affected":"1a6fdfb6955f8f3b4aae0f3c84c020f045fabe6b"}],"database_specific":{"versions":[{"introduced":"1.6"},{"last_affected":"2.0.10"}]}}],"versions":["v1.6","v1.6.1","v1.6.10","v1.6.11","v1.6.12","v1.6.2","v1.6.3","v1.6.4","v1.6.5","v1.6.6","v1.6.7","v1.6.8","v1.6.9","v2.0.0","v2.0.1","v2.0.10","v2.0.2","v2.0.3","v2.0.4","v2.0.5","v2.0.6","v2.0.7","v2.0.8","v2.0.9"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-34431.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}