A cryptographic break means simply reducing the number of complexity a Brute Force attack must take
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“Breaking a cipher simply means finding a weakness in the cipher that can be exploited with a complexity less than brute force. Never mind that brute-force might require 2128 encryptions; an attack requiring 2110 encryptions would be considered a break…simply put, a break can just be a certificational weakness: evidence that the cipher does not perform as advertised.” - Bruce Schneier