Surf Wiki
Save to docs
general/cryptographic-attacks

From Surf Wiki (app.surf) — the open knowledge base

Boomerang attack

Form of cryptanalysis

Boomerang attack

Form of cryptanalysis

Boomerang attack

In cryptography, the boomerang attack is a method for the cryptanalysis of block ciphers based on differential cryptanalysis. The attack was published in 1999 by David Wagner, who used it to break the COCONUT98 cipher.

The boomerang attack has allowed new avenues of attack for many ciphers previously deemed safe from differential cryptanalysis.

Refinements on the boomerang attack have been published: the amplified boomerang attack, and the rectangle attack.

Due to the similarity of a Merkle–Damgård construction with a block cipher, this attack may also be applicable to certain hash functions such as MD5.

The attack

The boomerang attack is based on differential cryptanalysis. In differential cryptanalysis, an attacker exploits how differences in the input to a cipher (the plaintext) can affect the resultant difference at the output (the ciphertext). A high probability "differential" (that is, an input difference that will produce a likely output difference) is needed that covers all, or nearly all, of the cipher. The boomerang attack allows differentials to be used which cover only part of the cipher.

The attack attempts to generate a so-called "quartet" structure at a point halfway through the cipher. For this purpose, say that the encryption action, E, of the cipher can be split into two consecutive stages, E0 and E1, so that E(M) = E1(E0(M)), where M is some plaintext message. Suppose we have two differentials for the two stages; say, :\Delta\to\Delta^* for E0, and :\nabla\to\nabla^* for E1−1 (the decryption action of E1).

The basic attack proceeds as follows:

  • Choose a random plaintext P and calculate P' = P \oplus \Delta.
  • Request the encryptions of P and P' to obtain C = E(P) and C' = E(P')
  • Calculate D = C \oplus \nabla and D' = C' \oplus \nabla
  • Request the decryptions of D and D' to obtain Q = E^{-1}(D) and Q' = E^{-1}(D')
  • Compare Q and Q'; when the differentials hold, Q \oplus Q' = \Delta.

Application to specific ciphers

One attack on KASUMI, a block cipher used in 3GPP, is a related-key rectangle attack which breaks the full eight rounds of the cipher faster than exhaustive search (Biham et al., 2005). The attack requires 254.6 chosen plaintexts, each of which has been encrypted under one of four related keys and has a time complexity equivalent to 276.1 KASUMI encryptions.

References

  • {{cite conference | book-title = 6th International Workshop on Fast Software Encryption (FSE '99) | access-date = 2007-02-05
  • {{cite conference | book-title = FSE 2000 | access-date = 2007-02-06
  • {{cite conference | book-title = Advances in Cryptology, Proceedings of EUROCRYPT 2001 | access-date = 2007-07-06 | archive-date = 2007-03-29 | archive-url = https://web.archive.org/web/20070329110058/http://citeseer.ist.psu.edu/biham01rectangle.html | url-status = dead
  • {{cite conference | book-title = FSE '02 | access-date = 2007-07-06 | archive-date = 2008-06-14 | archive-url = https://web.archive.org/web/20080614184616/http://citeseer.ist.psu.edu/504429.html | url-status = dead
  • {{cite conference | book-title = ASIACRYPT 2002
  • {{cite conference | book-title = Advanced Encryption Standard — AES, 4th International Conference, AES 2004 | access-date = 2007-07-06
  • {{cite conference | book-title = 9th Australasian Conference on Information Security and Privacy (ACISP 2004)
  • {{cite conference | book-title = FSE '05
  • {{cite conference | book-title = EUROCRYPT 2005 | access-date = 2007-02-16
  • {{cite conference | book-title = ASIACRYPT 2005 | access-date = 2007-07-06

References

  1. (2007). "Advances in Cryptology - CRYPTO 2007". Springer.
Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

cryptographic-attacks
Want to explore this topic further?

Ask Mako anything about Boomerang attack — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report