The vulnerability was dug up by Arnaud Ebalard, a security researcher with National Security Agency Information Systems (ANSSI) and formerly of the European Aeronautic Defence and Space Company (EADS) Siemens has several versions of its SIMATIC product but the S7-1500 family is used primarily in the manufacturing, food and beverage, and chemical industries. The German company confirmed last week that its still in the process of patching leftover Heartbleed bugs in its OpenSSL cryptographic software library.
Source: https://threatpost.com/siemens-patches-dos-vulnerability-in-simatic-s7-plc/107804/