I've 8 bytes before encryption (for example: 01 02 03 04 05 06 07 08
) and 8 bytes after DES encryption: 08 07 06 06 05 04 03 02 01
. Is it possible to calculate the key?
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1$\begingroup$ What you mean by DSA encryption? $\endgroup$– kelalakaSep 14, 2019 at 22:32
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$\begingroup$ DES key can be searched within 25 seconds with special hardware and $2^{56}$ is it is quite achievable by supercomputers $\endgroup$– kelalakaSep 14, 2019 at 22:43
1 Answer
A single p3.16xlarge EC2 instance is capable of evaluating $369\times10^9 \approx 2^{38}$ DES calls per second using hashcat.
This puts the maximum time to recover a key at around $2^{56} / 369\times10^9 / 3600 \approx 54$ hours. This costs a little over $1300 at current pricings.