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Is there any known instance of a Two Key TDES ever being successfully attacked (in real life), when the key is used to encrypt less than $2^{20}$ words?

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Also: $\:$ "Is there any ... ever being" used in real life? $\;\;\;\;$ – Ricky Demer Dec 28 '13 at 3:57

If we talk about key search attacks (rather than key compromise or/and side-channel attacks), the answer must be no, for the best known method is impractical.

On the other hand there has been numerous successful key-recovery attacks against devices using TDES, including on some that try hard to avoid it. One example here, another there.

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Hi, thanks a lot! That really helps. – user11123 Dec 31 '13 at 2:57

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