In Apache ActiveMQ 5.0.0 - 5.15.8, unmarshalling corrupt MQTT frame can lead to broker Out of Memory exception making it unresponsive.
https://www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html
https://www.oracle.com/security-alerts/cpujul2020.html
https://www.oracle.com/security-alerts/cpuapr2020.html
https://security.netapp.com/advisory/ntap-20190502-0006/
https://lists.debian.org/debian-lts-announce/2021/03/msg00005.html
https://lists.debian.org/debian-lts-announce/2021/03/msg00004.html
http://www.securityfocus.com/bid/107622
http://www.openwall.com/lists/oss-security/2019/03/27/2
http://activemq.apache.org/security-advisories.data/CVE-2019-0222-announcement.txt