A vulnerability has been identified in SIMATIC S7-1200 CPU V1 family (incl. SIPLUS variants) (All versions < V2.0.2), SIMATIC S7-1200 CPU V2 family (incl. SIPLUS variants) (All versions < V2.0.2). Affected controllers are vulnerable to capture-replay in the communication with the engineering software. This could allow an on-path attacker between the engineering software and the controller to execute any previously recorded commands at a later time (e.g. set the controller to STOP), regardless whether or not the controller had a password configured.
A capture-replay flaw exists when the design of the product makes it possible for a malicious user to sniff network traffic and bypass authentication by replaying it to the server in question to the same effect as the original message (or with minor changes).