Siemens SIMATIC S7-1500 CPU PLC devices with firmware before 1.5.0 allow remote attackers to cause a denial of service (defect-mode transition) via crafted HTTPS packets.
https://cert-portal.siemens.com/productcert/pdf/ssa-456423.pdf
http://www.siemens.com/innovation/pool/de/forschungsfelder/siemens_security_advisory_ssa-456423.pdf