Cryptology ePrint Archive: Report 2008/472

Practical attacks against WEP and WPA

Martin Beck and Erik Tews

Abstract: In this paper, we describe two attacks on IEEE 802.11 based wireless LANs. The first attack is an improved key recovery attack on WEP, which reduces the average number of packets an attacker has to intercept to recover the secret key. The second attack is (according to our knowledge) the first practical attack on WPA secured wireless networks, besides launching a dictionary attack when a weak pre shared key (PSK) is used. The attack works if the network is using TKIP to encrypt the traffic. An attacker, who has about 12-15 minutes access to the network is then able to decrypt an ARP request or response and send 7 packets with custom content to network.

Category / Keywords: cryptographic protocols / wep, wpa, tkip, rc4, korek, klein, ptw, wpa2, michael

Date: received 7 Nov 2008

Contact author: e_tews at cdc informatik tu-darmstadt de

Available format(s): PDF | BibTeX Citation

Version: 20081118:204358 (All versions of this report)

Short URL: ia.cr/2008/472

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