# Cryptanalysis of the Full Spritz Stream Cipher

@article{Banik2016CryptanalysisOT, title={Cryptanalysis of the Full Spritz Stream Cipher}, author={Subhadeep Banik and Takanori Isobe}, journal={IACR Cryptol. ePrint Arch.}, year={2016}, volume={2016}, pages={92} }

Spritz is a stream cipher proposed by Rivest and Schuldt at the rump session of CRYPTO 2014. It is intended to be a replacement of the popular RC4 stream cipher. In this paper we propose distinguishing attacks on the full Spritz, based on a short-term bias in the first two bytes of a keystream and a long-term bias in the first two bytes of every cycle of N keystream bytes, where N is the size of the internal permutation. Our attacks are able to distinguish a keystream of the full Spritz from a…

## 15 Citations

Spritz - a spongy RC4-like stream cipher and hash function

- Computer Science, MathematicsIACR Cryptol. ePrint Arch.
- 2016

This note reconsiders the design of the stream cipher RC4, and proposes an improved variant, which is called Spritz (since the output comes in ne drops rather than big blocks), which can be easily adapted for use as a cryptographic hash function, an encryption algorithm, or a message-authentication code generator.

Hardware Accelerator for Stream Cipher Spritz

- Computer ScienceSECRYPT
- 2016

The results show that the Spritz accelerator is significantly faster in encryption compared to the software implementation and fares weakly against hardware implementation of state-of-the-art hash functions and stream ciphers in terms of area-efficiency.

On data complexity of distinguishing attacks versus message recovery attacks on stream ciphers

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- 2015

We revisit the different approaches used in the literature to estimate the data complexity of distinguishing attacks on stream ciphers and analyze their inter-relationships. In the process, we…

Some Proofs of Joint Distributions of Keystream Biases in RC4

- Computer ScienceINDOCRYPT
- 2016

This paper provides detailed proofs of most of the biases found in the keystream bytes of the RC4 stream cipher when used in the TLS protocol, and unearth new biases based on the joint distributions of three consecutive bytes.

Enhancement of Advanced Encryption Standard (AES) Cryptographic Strength via Generation of Cipher Key-Dependent S-Box

- Computer Science, Mathematics
- 2018

A proposed method for constructing dynamic Cipher Key dependent S-box is introduced and implemented to encounter the possible attack on the fixed S -Box and passed the Avalanche, bit independence, non-linearity and balance test which proven its security.

Improved Secure Stream Cipher for Cloud Computing

- Computer ScienceICTERI Workshops
- 2020

Improved stream cipher based on RC4-128 has been developed and contains additional byte transformations in the PRN formation algorithm, an additional PRN and a new incoming message encryption algorithm using the generated threads that provide the cryptographic security of the proposed stream cipher.

Settling the mystery of Zr = r in RC4

- Computer ScienceCryptography and Communications
- 2018

This paper revisits the work of Mantin on finding the probability distribution of the RC4 permutation after the completion of the KSA and studies the bias of Zr = r, which has played an important role in the plaintext recovery attack proposed by Isobe et al. in FSE 2013.

Message Authentication (MAC) Algorithm For The VMPC-R (RC4-like) Stream Cipher

- Computer ScienceIACR Cryptol. ePrint Arch.
- 2019

An algorithm to compute Message Authentication Codes (MACs) along with VMPC-R encryption along with a simple method of transforming the MAC computation algorithm into a hash function.

Hypered Cryptographic Algorithm for LTE Data Confidentiality

- Computer Science, Mathematics
- 2016

Demonstrated that it does not add significant time to the encryption and decryption processes as the algorithm becomes more complex and it increases the avalanche effect providing more resistance to attacks and strength the randomization of the algorithm.

Application of Spritz Encryption in Smart Meters to Protect Consumer Data

- Engineering, Computer ScienceJ. Comput. Networks Commun.
- 2019

Spritz is an RC4-like algorithm designed to repair weak design decisions in RC4 to improve security, fast enough not to affect the operations of a smart meter and able to withstand brute force attacks on small keys.

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