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Observations on COMET



Daniel J. Bernstein, Henri Gilbert, Meltem Sonmez Turan


This note provides two observations on COMET, a second round candidate of the NIST lightweight cryptography standardization process. The first observation uses a long message to detect the use of weak keys, whereas the second observation focuses on the resistance of COMET against slide attacks. These observations do not invalidate the security claims of the designers
Cryptology ePrint Archive


COMET, distinguishers, Lightweight cryptography, slide attacks, weak subkeys


Bernstein, D. , Gilbert, H. and Sonmez Turan, M. (2020), Observations on COMET, Cryptology ePrint Archive, [online],, (Accessed May 30, 2024)


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Created November 15, 2020, Updated October 12, 2021