International Association
for Cryptologic Research

TWINE is a lightweight block cipher proposed at ECRYPT Workshop on Lightweight Cryptography 2011, Belgium.

The cipher consists of 36 rounds and has two versions TWINE-80 and TWINE-128 supporting key lengths of 80 and 128 bits, respectively.

The block length of the two versions is 64-bit.

In this paper, we present the first single-key attacks on the both versions of the cipher.

In these attacks, we use the recently developed biclique technique.

The complexities of the attacks on TWINE-80 and TWINE-128 are $2^{79.10}$ and $2^{126.82}$ respectively and the data requirement for the two attacks is $2^{60}$.