The issue is how fast the password can be broken. MD5 is a very fast hash, so even a relatively slow computer can do a lot of attempts very quickly.
Bcrypt, on the other hand, can be tuned to go as slow as you want. You can force it to take 250 milliseconds, regardless of how good or bad the password is.
And that is the fundamental flaw. Jungle Disk's key derivation makes it possible to crack your password in a reasonable time; bcrypt does not. Because of that decision, everybody's data is much less safe as a result (I'm referring to everybody's data in a statistical sense: the average password sucks and is easily broken in this scheme, so the average file is at risk).
As a provider of security software (like my company is doing), Jungle Disk should be doing everything it can to help users keep their data secure. Jungle Disk isn't doing that.
Bcrypt, on the other hand, can be tuned to go as slow as you want. You can force it to take 250 milliseconds, regardless of how good or bad the password is.
And that is the fundamental flaw. Jungle Disk's key derivation makes it possible to crack your password in a reasonable time; bcrypt does not. Because of that decision, everybody's data is much less safe as a result (I'm referring to everybody's data in a statistical sense: the average password sucks and is easily broken in this scheme, so the average file is at risk).
As a provider of security software (like my company is doing), Jungle Disk should be doing everything it can to help users keep their data secure. Jungle Disk isn't doing that.