Plaintext Recovery Attack of OCB2 [article]

Tetsu Iwata
2018 IACR Cryptology ePrint Archive  
Inoue and Minematsu [Cryptology ePrint Archive: Report 2018/1040] presented efficient forgery attacks against OCB2, and Poettering [Cryptology ePrint Archive: Report 2018/1087] presented a distinguishing attack. In this short note, based on these results, we show a plaintext recovery attack against OCB2 in the chosen plaintext and ciphertext setting. We also show that the decryption oracle of the underlying block cipher can be simulated. This complements the simulation of the encryption oracle
more » ... f the block cipher by Poettering in [Cryptology ePrint Archive: Report 2018/1087].
dblp:journals/iacr/Iwata18 fatcat:horv6ue4nbe6bgfglcinkgk6ze