Cryptanalysis of the Cellular Encryption Algorithm

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David A. Wagner, Bruce Schneier, John Kelsey

Published: 1997, Last Modified: 14 May 2025CRYPTO 1997EveryoneRevisionsBibTeXCC BY-SA 4.0
Abstract: This paper analyzes the Telecommunications Industry Association's Cellular Message Encryption Algorithm (CMEA), which is used for confidentiality of the control channel in the most recent American digital cellular telephony systems. We describe an attack on CMEA which requires 40–80 known plaintexts, has time complexity about 224–232, and finishes in minutes or hours of computation on a standard workstation. This demonstrates that CMEA is deeply flawed.