# On Cipher-Dependent Related-Key Attacks in the Ideal-Cipher Model

@inproceedings{Albrecht2011OnCR, title={On Cipher-Dependent Related-Key Attacks in the Ideal-Cipher Model}, author={Martin R. Albrecht and Pooya Farshim and Kenneth G. Paterson and Gaven J. Watson}, booktitle={IACR Cryptol. ePrint Arch.}, year={2011} }

Bellare and Kohno introduced a formal framework for the study of related-key attacks against blockciphers. They established sufficient conditions (output-unpredictability and collision-resistance) on the set of related-key-deriving (RKD) functions under which an ideal cipher is secure against related-key attacks, and suggested this could be used to derive security goals for real blockciphers. However, to do so requires the reinterpretation of results proven in the idealcipher model for the…

## 32 Citations

The Related-Key Security of Iterated Even-Mansour Ciphers

- Computer Science, MathematicsFSE
- 2014

It is shown that the simplest one-round EM cipher is strong enough to achieve non-trivial levels of RKA security even under chosen-ciphertext attacks and that three rounds can boost security to resist chosen-plaintext attacks.

Towards a Characterization of the Related-Key Attack Security of the Iterated Even-Mansour Cipher

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

A far simpler proof is presented which uses techniques similar to those used by Cogliati and Seurin in their proof that the four-round Even-Mansour cipher is secure against XOR related-key attacks—a special case of the result of Farshim and Proctor.

The design and analysis of symmetric cryptosystems

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- 2015

A general forgery attack against the related message authentication schemes is described, as well as providing a common description of all known attacks against such schemes, and greatly expanding the number of known weak keys.

On the Related-Key Attack Security of Authenticated Encryption Schemes

- Computer Science, MathematicsIACR Cryptol. ePrint Arch.
- 2022

This work revisits the common approach to construct AEAD from encryption and message authentication and extends the traditional security notion of AEAD to the RKA setting and considers an adversary that can tamper with the key Ke and Km of the underlying encryption and MAC, respectively.

A quantum related-key attack based on Bernstein-Vazirani algorithm

- Computer Science, MathematicsQuantum Inf. Process.
- 2020

This work shows that related-key attack is quite powerful when combined with quantum algorithms, and provides some guidance for the design of block ciphers that are secure against quantum adversaries.

Insuperability of the Standard Versus Ideal Model Gap for Tweakable Blockcipher Security

- Computer Science, MathematicsCRYPTO
- 2017

It is proved that if this proof technique is adopted, tweak-rekeying will not help in achieving optimal security: if 2^{\sigma n/(\sigma +1)}\) is the best one can get without tweak- rekeying, optimal \(2^n\) provable security with tweak-Rekeying is impossible.

Cryptography Secure Against Related-Key Attacks and Tampering

- Computer Science, MathematicsIACR Cryptol. ePrint Arch.
- 2011

A broad and high level picture of the way achievability of RKA security varies across primitives is presented, showing, in particular, that some primitives resist "more" RKAs than others.

Security of Symmetric Primitives against Key-Correlated Attacks

- Computer Science, MathematicsIACR Cryptol. ePrint Arch.
- 2019

This work provides feasibility results in the ideal-cipher model for KCAs and shows that 3-round Even–Mansour is KCA secure under key offsets in the random-permutation model, which allows for a unified treatment of RKA and KDM security in idealized models of computation.

Encryption in the presence of key-dependent messages and related-key attacks

- Computer Science, Mathematics
- 2015

This thesis investigates enhanced adversarial models for encryption for scenarios where established notions of security are not sufficient to accurately model the capabilities of real-world adversaries, and presents a composition theorem showing how to generically achieve RKA-KDM security.

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