In massive machine-type communications (mMTC). user-specific and non-orthogonal signatures can be assigned to wireless devices for uplink grant-free access. In this paper. we analyze the performance of signature-based grant-free random access in the presence of an adversary. https://www.bekindtopets.com/flash-find-Winmau-Firestorm-Steel-Tip-Darts-24gm-special-save/