I wonder how long it will take to crack 16 character alphanumeric WinRAR password for a mini supercomputer. As far as I know graphic cards are preferred over CPUs to crack passwords nowadays. If we consider that the cracker (law enforcment) uses the latest technologies to crack the RAR password and has pretty much computing power how long it will take for him to crack the password?
A completely random alphanumeric password of length 16 has an entropy of 95 bits (16*log2(2*26+10)). I forgot the exact value, but I think rar uses around 100k iterations for its KDF, increasing the security level by about 17 bits, resulting in an effective security level of 112 bits.
With standard GPUs breaking this would cost around $1019. Custom hardware shaves off a factor 100 or so, still giving you a cost of $1017. Even if Moore's law continues, it'll take several decades until this is remotely feasible.