Matt Johnston Dropbear SSH server 0.47 and earlier, as used in embedded Linux devices and on general-purpose operating systems, allows remote attackers to cause a denial of service (connection slot exhaustion) via a large number of connection attempts that exceeds the MAX_UNAUTH_CLIENTS defined value of 30.
https://exchange.xforce.ibmcloud.com/vulnerabilities/25075
http://www.securityfocus.com/bid/17024
http://www.securityfocus.com/archive/1/426999/100/0/threaded