Directory traversal vulnerability in the Runtime Toolkit in CODESYS Runtime System 2.3.x and 2.4.x allows remote attackers to read, overwrite, or create arbitrary files via a .. (dot dot) in a request to the TCP listener service.
http://www.us-cert.gov/control_systems/pdf/ICSA-13-011-01.pdf
http://www.securityfocus.com/bid/56300