The WebNavigator server in Siemens SIMATIC WinCC before 7.3, as used in PCS7 and other products, allows remote attackers to obtain sensitive information via an HTTP request.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2014-4601
http://www.siemens.com/innovation/pool/de/forschungsfelder/siemens_security_advisory_ssa-214365.pdf