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PwdRsch

9 karma · joined January 8, 2013

Hi, I'm Bruce K. Marshall. I've been conducting and gathering research on passwords and authentication systems since the late 90's. I started the PasswordResearch.com site as a way to share my collection of information and to encourage more collaboration between academics and IT practitioners.

I'm here to continue learning about the questions and problems people have with authentication as well as contributing my own experiences. You can also find me on Twitter @PwdRsch.

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PwdRsch··on New NIST password guidelines: don't require character types or rotation
Yep, unfortunately for passphrases the maximum acceptable password length on web sites tends to be the #1 factor limiting their use. I created sample passphrases and tried them on a handful of different sites to measure the problem. See starting slide 31 in this presentation (PDF): http://www.passwordresearch.com/files/How%20Secure%20Are%20M...
PwdRsch··on New NIST password guidelines: don't require character types or rotation
Here you go: https://security.stackexchange.com/questions/62832/is-the-of...
PwdRsch··on AdultFriendFinder was hacked
They do try changing the capitalization of only the first character, but also invert the capitalization of all the characters in the supplied password. http://www.zdnet.com/article/facebook-passwords-are-not-case...
PwdRsch··on Analyzing the Patterns of Numbers in 10M Passwords (2015)
Some of the latest research on this technique:

Fast, Lean, and Accurate: Modeling Password Guessability Using Neural Networks https://www.ece.cmu.edu/~lbauer/papers/2016/usenixsec2016-ne...

PwdRsch··on On Phone Numbers and Identity
Yes. They didn't need to know his strong password to log on, they just needed access to his mobile phone SMS in order to complete the account recovery process and change his account password to a value they chose.
PwdRsch··on But why can't I send people their passwords?
It is complete idiocy to use passwords across services. Utter insanity. It is the worst possible practice imaginable, and is never, ever excusable.

It's one thing to argue for improving people's password practices, but please don't pretend that there's no reason for their behavior. The vast majority of people who share passwords between sites experience no repercussions from their choice. And choosing not to create a new password for every site saves them time and potential frustration.

That's the human nature part, to assess the risk of behavior and change it only if future experiences show that the costs associated with that behavior are too high. Since most people don't experience the disadvantages and do experience the benefits this behavior continues.

We can encourage more people to avoid this behavior by explaining the potential impacts and providing accurate estimates of the risk they're taking. We can offer alternatives to password reuse, like using a password manager. But ultimately they are still going to weigh their perception of the risk and benefits to make their own decision.

PwdRsch··on How crackers ransack passwords like “qeadzcwrsfxv1331”
Here's what it says in the "How I became a password cracker" article (http://arstechnica.com/security/2013/03/how-i-became-a-passw...) on Ars from March:

"Dan suggested that, in the interest of helping me get up to speed with password cracking, I start with one particular easy-to-use forum and that I begin with "unsalted" MD5-hashed passwords, which are straightforward to crack. And then he left me to my own devices. I picked a 15,000-password file called MD5.txt, downloaded it, and moved on to picking a password cracker."

My guess is that the forum he mentions was the insidepro.com web site, since it is a popular password hash sharing site. A quick search there found several attached files named MD5.txt, but none seemed to be the right size or have the right hashes. However, a search for hashes mentioned in the article found this file (http://forum.insidepro.com/download.php?id=12783&sid=160...), which contains 16,880 (instead of the 16,449 hashes listed in the Ars article) and at least 3 of the MD5 hashes specifically mentioned in the article.

There's a good chance this is the same file or close to it, but you'd have to try matching it with more of the hashes from the article to know for sure.

PwdRsch··on How crackers ransack passwords like “qeadzcwrsfxv1331”
Telling people to use passphrases is a great recommendation, but you still have to spend some time teaching them how to use passphrases effectively. In the article they list several passphrases that were cracked, such as "sleepingwithsirens", "gonewiththewind1", and "momof3g8kids". So if a user chooses "ijustbluemyself" thinking that it's a great choice they are likely to be disappointed if a skilled cracker gets access to their password hash.

My basic suggestions are to choose 4+ words that are not a common phrase, song name, quote, etc. And make sure you still use both lowercase and uppercase letters, plus throw in some symbols in non obvious places (e.g., don't convert your a's into @ signs). It doesn't need to be as random as a shorter password, but it still shouldn't look like a normal sentence.

PwdRsch··on How crackers ransack passwords like “qeadzcwrsfxv1331”
There actually has been research on how to split passwords across multiple servers (one example http://www.passwordresearch.com/papers/paper270.html), and RSA is currently marketing a commercial product that does this. While I agree that most people probably aren't concerned enough about password exposure to do this, there are effective solutions to accommodate those that are.
PwdRsch··on How I 'stole' $14 million from a bank: A security tester's tale
I used to do this same thing and never heard about pen testing firms being sued by their client. Most likely he was spinning a yarn.

It is more likely that a security consulting firm will be sued if they report no issues and the bank is later compromised.

PwdRsch··on How people respond to being filmed (with devices like Google glass)
AJ Jacobs at Esquire magazine wrote about his experience doing something similar back in December: http://www.esquire.com/features/overly-documented-life-0113
PwdRsch··on To Keep Passwords Safe from Hackers, Just Break Them into Bits
That's simply not true. Rainbow tables are still the first choice of many people trying to crack passwords, with brute force or hybrid attacks as a follow up after the common passwords have been found.

It doesn't hurt that there are a lot of rainbow tables available to access for free on the Internet.