Your New Year’s Resolution–Pick Better Passwords
by Ben Gross
As we near the end of 2011, I can’t help but think this is the year I had the most trouble telling the difference between actual news stories and pieces from “America’s Finest News Source”, The Onion. As I write this article, details are still unfolding from the data breach at the private intelligence firm Stratfor.
According to reports, the Stratfor hackers found a weakly protected database of usernames and passwords and an unencrypted database of credit card information. The hackers proceeded to make donations to charitable organizations with the credit cards in the database. As any story benefits from more absurdity, there were claims and counter claims of whether or not the attack was associated with Anonymous, the discerning hacker’s first choice of affiliation.
According to Identity Finder, the Stratfor database contained approximately 44,000 hashed passwords in the database, roughly half of which have already been exposed. Unfortunately, another 20,000 or passwords on pastebin would not even be newsworthy, if it were not for the notoriety of Stratfor. Note: if you think you might have been on the list of compromised accounts in the Stratfor database, you can check at Dazzlepod.
There is plenty of blame to go around. First, Stratfor stored user passwords as basic unsalted MD5 hashes, which is simply irresponsible. There are well-regarded and widely-available solutions for storing passwords such as bcrypt, which is nicely summarized in Coda Hale’s How To Safely Store A Password. Secondly, and more importantly, storing customer’s credit cards in clear text is unconscionable. Never mind the question of why on earth Stratfor stored CCVs in their database, which is never OK.
Given the recent attacks against Sony, Gawker, HBGary Federal, and Infragard Atlanta, one could reasonably expect that Stratfor would pay more attention to the operational security side of their business. To put the Stratfor hack in a more global context, the 2011 Verizon Data Breach Investigations Report aggregates data from Verizon RISK, the U.S. Secret Service and the Dutch High Tech Crime Unit. DataLossDB Statistics collected data from open sources including news reports, Freedom of Information Act (FOIA) requests, and public records. These reports give a more nuanced breakdown of the types of breaches and data exposed across many industries.
As much as it pains me to blame the victim, a great many of the subscribers to Stratfor’s service, clearly could and should have picked better passwords. According to Stratfor Confidential Customer’s passwords analysis, we could start with the 418 users who picked “stratfor” as their password or even the 71 users who picked “123456.” The database was full of weak passwords, which was why the clear text of nearly half the passwords followed in a post shortly after the original password hashes appeared online.
In Data Evaporation and the Security of Recycled Accounts, I described how passwords for email accounts are frequently the weak link in the security chain. It is common for sites to allow users to reset their passwords to the email address listed on the account. This means that a compromised email account may be the only method an attacker needs to gain access to other accounts.
In my dissertation interviews, I talked with people about how they managed their accounts and passwords. Many of my interviewees told me they effectively had 2-3 passwords they used for most accounts with some minor variations due to password complexity rules. The interviewees frequently reported using a set of low, medium, and high security passwords. Unfortunately, the email accounts were often given the low security passwords.
It pains me to think how many of the customers in Stratfor’s database likely reuse the same password on multiple sites. In Measuring password re-use empirically, Joseph Bonneau analyzed the overlap between rootkit.com and gawker.com passwords in addition to other studies and found a wide-spread ranging from 10% to 50% overlap. Even with 10% overlap, there are significant benefits from leveraging one exploited password database to compromise another. As always, XKCD keeps track of the pulse of the internet and has informative comics for both Password Reuse and Password Strength.
Realistically, it’s getting to the point where unless you have a pretty fantastic password, if your password is in a database of poorly hashed passwords then someone with a bit of time can discover it. Why is that you might ask? Whitepixel the purveyors of fine open source GPU accelerated password hashing software report that it currently achieves 33.1 billion password/sec on 4 x AMD Radeon HD 5970 for MD5 hashes. This is fast enough to make rainbow tables (pre-computed hashes for a dictionary attack) much less compelling. If the attacker has any additional personal information this significantly increases the chance of a successful attack since so many people use bits of personal information in their passwords. Bruce Schneier describes commercial software that exploits personal information when attempting compromise password hashes in Secure Passwords Keep You Safer.
In general, unless your password or pass phrase is quite long you are far better off with a long randomly generated string that you manage with a password manager. There are many good options including my personal favorite 1Password, UsableLogin, LastPass, RoboForm, or the open source projects PwdHash or Password Safe. PasswordCard is a nice alternative if you would prefer a solution you can always carry with you that does not require any dependencies besides what you can carry in your wallet.
Unfortunately, none of the password managers are magic. You will still have to deal with a depressingly large number of services that force you to choose poor passwords with arbitrary restrictions. Troy Hunt names some offenders in the Who’s who of bad password practices – banks, airlines and more. Still, if you simply use a password manager and different password with each service, you will dramatically limit any potential damage, as an attacker cannot reuse your password on another service.
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