  For the last several years, the embedding of hidden information by
steganographic techniques in network communications is increasingly used by
attackers in order to obscure data infiltration, exfiltration or command and
control in IT (information technology) and OT (operational technology) systems.
Especially industrial control systems (ICS) and critical infrastructures have
increased protection requirements. Currently, network defense mechanisms are
unfortunately quite ineffective against novel attacks based on network
steganography. Thus, on the one hand huge amounts of network data with
steganographic embedding is required to train, evaluate and improve defense
mechanisms. On the other hand, the real-time embedding of hidden information in
productive ICS networks is crucial due to safety violations. Additionally it is
time consuming because it needs special laboratory setup. To address this
challenge, this work introduces an embedding concept to gene ate synthetic
steganographic network data to automatically produce significant amounts of
data for training and evaluation of defense mechanisms. The concept enables the
possibility to manipulate a network packet wherever required and outperforms
the state-of-the-art in terms of embedding pace significantly.
