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net.wars: Insecure at any speed

"I have always depended on the kindness of strangers," Blanche says graciously to the doctor hauling her off to the nuthouse at the end of Tennessee Williams' play A Streetcar Named Desire. And while she's quite, quite mad in her genteel Old Southern delusional way she is still nailing her present and future situation, which is that she's going to be living in a place where the only people who care about her are being paid to do so (and given her personality, that may not be enough).

Of course it's obvious to anyone who's lying in a hospital bed connected to a heart monitor that they are at the mercy of the competence of the indigenous personnel. But every discussion of computer passwords tends to go as though the problem is us. Humans choose bad passwords: short, guessable, obvious, crackable. Or we use the same ones everywhere, or we keep cycling the same two or three when we're told to change them frequently. We are the weakest link.

And then you read this week's stories that major sites for whom our trust is of business-critical importance - LinkedIn, eHarmony, and Last.fm" - have been storing these passwords in such a way that they were vulnerable to not only hacking attacks but also decoding once they had been copied. My (now old) password, I see by typing it into LeakedIn for checking, was leaked but not cracked (or not until I typed it in, who knows?).

This is not new stuff. Salting passwords before storing them - the practice of adding random characters to make the passwords much harder to crack - has been with us for more than 30 years. If every site does these things a little differently, the differences help mitigate the risk we users bring upon ourselves by using the same passwords all over the place. It boggles the mind that these companies could be so stupid as to ignore what has been best practice for a very long time.

The leak of these passwords is probably not immediately critical. For one thing, although millions of passwords leaked out, they weren't attached to user names. As long as the sites limit the number of times you can guess your password before they start asking you more questions or lock you out, the odds that someone can match one of those 6.5 million passwords to your particular account are…well, they're not 6.5 million to one if you've used a password like "password" or "1233456", but they're small. Although: better than your chances of winning the top lottery prize.

Longer term may be the bigger issue. As Ars Technica notes, the decoded passwords from these leaks and their cryptographically hashed forms will get added to the rainbow tables used in cracking these things. That will shrink the space of good, hard-to-crack passwords.

Most of the solutions to "the password problem" aim to fix the user in one way or another. Our memories have limits - so things like Password Safe will remember them for us. Or those impossible strings of letters and numbers are turned into a visual pattern by something like GridSure, which folded a couple of years ago but whose software and patents have been picked up by CryptoCard.

An interesting approach I came across late last year is sCrib, a USB stick that you plug into your computer and that generates a batch of complex passwords it will type in for you. You can pincode-protect the device and it can also generate one-time passwords and plug into a keyboard to protect against keyloggers. All very nice and a good idea except that the device itself is so *complicated* to use: four tiny buttons storing 12 possible passwords it generates for you.

There's also the small point that Web sites often set rules such that any effort to standardize on some pattern of tough password is thwarted. I've had sites reject passwords for being too long, or for including a space or a "special character". (Seriously? What's so special about a hyphen?) Human factors simply escape the people who set these policies, as XKCD long ago pointed out

But the key issue is that we have no way of making an informed choice when we sign up for anything. We have simply no idea what precautions a site like Facebook or Gmail takes to protect the passwords that guard our personal data - and if we called to ask we'd run into someone in a call center whose job very likely was to get us to go away. That's the price, you might say, of a free service.

In every other aspect of our lives, we handle this sort of thing by having third-party auditors who certify quality and/or safety. Doctors have to pass licensing exams and answer to medical associations. Electricians have their work inspected to ensure it's up to code. Sites don't want to have to explain their security practices to every Sheldon and Leonard? Fine. But shouldn't they have to show *someone* that they're doing the right things?