Presentation 2007-11-22
A Key Recovery Attack on WEP with Less Packets
Toshihiro OHIGASHI, Hidenori KUWAKADO, Masakatu MORII,
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Abstract(in Japanese) (See Japanese page)
Abstract(in English) E. Tews, R. Weinmann, and A. Pyshkin have recently shown a key recovery attack on WEP (called the PTW attack). The PTW attack recovers a 104-bit secret key from the first 15 bytes of a keystream, which is obtained from the output of WEP. It recovers the secret key with a probability of 0.5 when 40,000 packets are given, or with a probability of 0.95 when 85,000 packets are given. Their attack is one of the most effective attack on WEP. This paper proposes a key recovery attack, which uses the first 30 bytes of the keystream. In order to use the 16-30th bytes of the keystream for the attack, we give two processes. Our attack halves the number of packets for similar probability that the 104-bit secret key is recovered by the PTW attack. In particular, our attack can recover the secret key with a non-negligible probability when the number of packets is small, for example, 5,000, 7,500, or 10,000. Therefore, even low-traffic communication on WEP allows an attacker to recover a secret key.
Keyword(in Japanese) (See Japanese page)
Keyword(in English) cryptanalysis / key recovery attack / stream cipher / RC4 / WEP
Paper # ISEC2007-109,OIS2007-81
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Conference Information
Committee ISEC
Conference Date 2007/11/15(1days)
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Language ENG
Title (in Japanese) (See Japanese page)
Sub Title (in Japanese) (See Japanese page)
Title (in English) A Key Recovery Attack on WEP with Less Packets
Sub Title (in English)
Keyword(1) cryptanalysis
Keyword(2) key recovery attack
Keyword(3) stream cipher
Keyword(4) RC4
Keyword(5) WEP
1st Author's Name Toshihiro OHIGASHI
1st Author's Affiliation Graduate School of Science and Technology, Kobe University()
2nd Author's Name Hidenori KUWAKADO
2nd Author's Affiliation Graduate School of Engineering, Kobe University
3rd Author's Name Masakatu MORII
3rd Author's Affiliation Graduate School of Engineering, Kobe University
Date 2007-11-22
Paper # ISEC2007-109,OIS2007-81
Volume (vol) vol.107
Number (no) 346
Page pp.pp.-
#Pages 8
Date of Issue