Cryptology ePrint Archive: Report 2016/697

Ciphertext Forgery on HANUMAN

Damian Vizár

Abstract: HANUMAN is a mode of operation of a keyless cryptographic permutation for nonce-based authenticated encryption with associated data, included among the modes bundled in the PRIMATEs candidate in the currently ongoing CAESAR competition. HANUMAN is a sponge-like mode whose design and security argument are inspired by the SpongeWrap construction. We identify a flaw in the domain separation of HANUMAN, and show how to exploit it to efficiently produce ciphertext forgeries.

Category / Keywords: secret-key cryptography / Authenticated encryption, PRIMATEs, ciphertext forgery, CAESAR competition

Date: received 12 Jul 2016

Contact author: damian vizar at epfl ch

Available format(s): PDF | BibTeX Citation

Version: 20160713:135448 (All versions of this report)

Short URL: ia.cr/2016/697