Chybový útok na šifru CSA pro šifrování videa v systému Digital Video Broadcasting (placená televize v Evrop?)
08.11.2004
The Common Scrambling Algorithm (CSA) is used to encrypt
streams of video data in the Digital Video Broadcasting (DVB)
system. The algorithm uses a combination of a stream and a block cipher,
apparently for a larger security margin. However these two algorithms
share a common key.
In this paper we present a fault attack on the block cipher which can be
launched without regarding the stream cipher part. This attack allows us
to reconstruct the common key and thus breaks the complete Algorithm.
The DVB Common Scrambling Algorithm is used to secure MPEG-2 transport
streams. These are used for example for digitally transmitted Pay-TV in Europe.
The algorithm was specified by ETSI and adopted by the DVB consortium in
May 1994.