SKINNY-AEAD and SKINNY-Hash: NIST LWC Second-round Candidate Status Update

A comprehensive list of third-party analysis on SKINNY-128-256 and SKINNY-128-384 is documented in [2, §5.3]. In short, both variants remain secure with at least 50% security margin. To the best of our knowledge, there are two new third-party analysis [5, 3] that is not included. [5] presented a related-tweakey rectangle attack on 28-round SKINNY-128-384 (previous best was 27-round) under a specifc setup on the tweakey and with time, data and memory complexity of 2315.25, 2122 and 2122.32 respectively. The authors also claimed a relatedtweakey attack on SKINNY-AEAD-M1 with 24-round SKINNY-128-384. However, as discussed