Comment by tsimionescu
6 months ago
Either way, password lengths are exposed in virtually all scenarios except the Unix Terminal - and have caused 0 issues in practice. The default of hiding password inputs really is useless security theater, and always has been.
The crazier part is Ubuntu using a pre-1.0 software suite instead of software that has been around for decades. The switch to Rust coreutils is far too early.
> and have caused 0 issues in practice
Do you have some data to back that up? Because I doubt it’s literally 0. I make this point because we shouldn’t talk about absolutes when discussing security.
Fo example, Knowing a password length does make it easier to crack a password. So it’s not strictly “security theatre”.
So the real question isn’t whether it has any security benefit; it’s more is the convenience greater than the risk it introduces.
Framing it like this is important because for technical users like us on HN, we’d obviously mostly say the convenience is negligible and thus are more focused on the security aspect of the change.
But for the average Desktop Ubuntu user, that convenience aspect is more pronounced.
This is why you’re going to see people argue against this change on HN. Simply put, different people have different risk appetites.
Knowing password length makes it easier to crack an insecure password.
The SHA256 hash of a 6-symbol diceware password, where each symbol has its first letter capitalized and the rest lowercase, with 1! appended for compliance with misguided composition rules is 540b5417b5ecb522715fd4bb30f412912038900bd4ba949ea6130c8cb3c16012. There are 37 octets in the password. You know the length. You know the composition rules. You have an unsalted hash. It's only 77 or so bits of entropy. Get cracking, I'll wait.
Knowing that user passwords have to be manually keyed, I don’t think the average person will have a 37 character password set ;)
Typically they’re between 8 and 12 characters. Usually contain dictionary terms, with the first character capitalised and a numeric value at the end with an exclamation mark.
If you know a little bit of information about the individual (which you likely will if you’re in a position to shoulder surf) then you can easily guess at personal details that individual might use (kids names, favourite movie, sports team, that kind of stuff) which also helps narrow the search field too.
Now I’m not saying that this will apply for everyone. But you can see how knowing the password length combined with another piece of information suddenly increases the statistical probability of cracking some passwords.
And this comes back to my earlier point about how security isn’t about absolutes. It’s about probabilities and risk. So there isn’t going to be a universal truth about whether this decision is correct for everyone or not.
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