In smart distribution networks, an essential responsibility of system operators is to effectively respond to the detected cyberattacks in order to prevent any possible blackout. This paper proposes a reaction framework for the distribution system operator (DSO) to respond to decentralized cyberattacks implemented on several distributed generation (DG) retailers, electric vehicle (EV) retailers, and demand response (DR) retailers. Due to the false data injections on the clients of DG / EV / DR retailers, wrong aggregated data will be submitted to the DSO. If a proper response is not provided, system has to rely on the targeted market participants which can result in congestion / blackout. As a result, we propose a real-time smart distribution network reconfiguration (RSDNR) framework for DSO to result in a system topology such that 1) minimum reliance on attacked retailers is required for system operation and 2) convenience of market participants is minimally affected by the administrative reaction of DSO. The effectiveness of the proposed scheme is validated on a well-known 136-bus distribution system modified with DGs and flexible loads which can provide DR.