There is an increasing trend to operate vehicles (automobiles and drones) in a swarm setting. To ensure the safety of their users, it is critical to verify the integrity of the software running on these vehicles. In the existing literature, the conventional software attestation developed for one node (vehicle) has been trivially extended for each node in a swarm. In this work, we explore the question of whether we could reduce the total computational cost of the software attestation of the swarm. To that end, we propose a novel program integrity verification mechanism for a single-node setting. The proposed mechanism is inherently designed considering the scalability in a swarm setting. Our initial results demonstrate that the proposed mechanism when utilized for a swarm significantly reduces the total swarm attestation time as compared to the prior art.