How can high-grade encryption be cracked?
By definition, it can’t be – but its keys can. Some techniques used, in increasing order of cost/risk are: (1) exploiting operator errors (e.g. recovering a password from its repeated use with slight variation in less secure applications which can be cracked); (2) dumpster diving for papers on which the operator may have doodled hints to the area of interest s/he used to pick a password, and using them to guide automated dictionary attacks; (3) bribery or rubber hose cryptanalysis (duress). NOTE: High-grade encryption cannot be reversed without the keying information. Its very high work-factor shifts the focus of attack from “cracking the cryptosystem” to “cracking the owner.” High-value data requires a total security plan, of which encryption is only an element.
