A method for first path acceptance for secure ranging includes determining a Channel Impulse Response (CIR) of a communication channel for a plurality of channel taps. Each channel tap corresponds to a respective one of a plurality of time slots of the CIR, wherein the CIR includes a plurality of estimated CIR values. A statistical characteristic is extracted from the estimated CIR values within a temporal range of the channel taps. The statistical characteristic is compared to a reference value to detect a distance decreasing attack.