This paper explores primary user emulation attack (PUEA) impact on spectrum sensing (SS), sum secondary user (SU) throughput and energy harvesting (EH) in cognitive radio network (CRN). Cognitive radio (CR) system model consists of a set of transmit-receive node pairs, one fusion center (FC) and one PUEA node. At the initial time slot of the frame, simultaneous EH and spectrum sensing (SS) are done through power splitting (PS) mode. Then based on SS decision, at the FC, CR transmit nodes either perform EH or transmit data in time division mode. Closed form expressions of the optimal sensing duration and transmit power for each SU are found while maximizing the sum SU throughput under the constraints of SS reliability, energy causality on each SU, interference at PU and outage probability on individual SU link. Simulation results show that ∼20% increase in PUEA power enhances the throughput ∼9.76% and residual energy ∼0.31% while meeting the detection and false alarm probabilities 0.95 and 0.05, respectively.