The integrated web server on Siemens SCALANCE X-200 switches with firmware before 4.5.0 and X-200IRT switches with firmware before 5.1.0 does not properly enforce authentication requirements, which allows remote attackers to perform administrative actions via requests to the management interface.
https://cert-portal.siemens.com/productcert/pdf/ssa-176087.pdf
http://www.siemens.com/innovation/pool/de/forschungsfelder/siemens_security_advisory_ssa-176087.pdf