Comment by SamBam
4 years ago
> Someone adversarial to me could bribe a number of people to get answers to 10 different password hints.
OP's hints are probably more generous than they need to be. (Indeed, knowing that password is name + flower + name + two-word-thing, plus the fact that there is no limit to the speed you could brute-force this, means that someone could probably make a custom dictionary and break this in a couple days.)
But you can easily have hints and make it harder. In Evernote I store a few passwords to things, and the hints are more opaque ("grey" refers to my old grey cat, for instance) but they're also all prepended with a 15-character master password that changes in subtle ways depending on the service they're used for. This isn't in the hint, it's just in my head.
>knowing that password is name + flower + name + two-word-thing, plus the fact that there is no limit to the speed you could brute-force this, means that someone could probably make a custom dictionary and break this in a couple days
Off topic, but in principle a sufficiently expensive key derivation could guard against this, right? Is there a reason why it isn't done? I wouldn't mind waiting a few minutes for my identity document to decrypt if I hardly ever access it. In that case the usability benefit of a fast key derivation algorithm seems minor.
It wouldn't even be hard to expose this functionality via a user interface -- say when a user is setting up a Portable Secret, let them click to select a security level between "low security" and "high security", where each security level corresponds to an estimated number of minutes it will take the secret to decrypt on a modern PC. Seems like it would make intuitive sense to grandma.
And with regard to the software vulnerabilities topic discussed above, as long as we're waiting a few minutes, we might as well make use of multiple key derivation algorithms in case one or more of them is shown to be weak.
I have things like this in my head too and I wonder if I’ll forget when I get elderly.
or bonked on the head. it's a scary thought.
I've thought of that too, perhaps I write them down in a sealed envelope and tell my spouse or kid, only open in an emergency. I feel it's pretty certain these non-software engineers in my family have less security notions than I do, so I have reserved some passwords that are in my head.
I signed up for the gmail "I died, here is my account" option.
1 reply →
Do you trust Evernote? I think the employee are able to read private notes
Yes, they can. Evernote, the company, really pushes their "everything is encrypted" mantra, but you have to really push them to get them to admit that it's only encrypted in transit. On their server storage, the data is encrypted using their key, so if someone stole a drive or a disk image they wouldn't be able to read it, but any number of people at Evernote would have full access to anyone's data.
That's why my hints are opaque and exclude the long, mutable master password.