A Decade After Stuxnet: How Siemens S7 is Still an Attacker's Heaven 

...In our presentation, we reverse-engineer the Siemens S7-1500 Software Controller PLC up to the communication protocol and show the violation of fundamental security principles. We show that substantial efforts have been put into obfuscating communication and modifying established cryptography primitives without increasing the effective security level....
By: Tom Dohrmann , Colin Finck
Full Abstract and Presentation Materials:
www.blackhat.c...