Multiple unspecified vulnerabilities on the Rockwell Automation AB Micrologix 1100 and 1400 controllers allow remote attackers to obtain privileged access or cause a denial of service (halt) via unknown vectors.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2009-3711
http://www.securityfocus.com/archive/1/508946/100/0/threaded