RuggedCom Rugged Operating System (ROS) 3.10.x and earlier has a factory account with a password derived from the MAC Address field in the banner, which makes it easier for remote attackers to obtain access by performing a calculation on this address value, and then establishing a (1) TELNET, (2) remote shell (aka rsh), or (3) serial-console session.
https://exchange.xforce.ibmcloud.com/vulnerabilities/75120
http://www.wired.com/threatlevel/2012/04/ruggedcom-backdoor/
http://www.securityfocus.com/bid/53215
http://www.kb.cert.org/vuls/id/MAPG-8RCPEN
http://www.kb.cert.org/vuls/id/889195