A set of requirements regarding password creation, storage, and usage. These requirements often constrain several characteristics of passwords. So, a password policy is a set of rules designed to enhance computer security by encouraging users to employ strong passwords and use them properly.

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Sequential password updates

Let's say I have a reasonable KDF, and that I make users change their passwords periodically and keep some old password hashes to prevent password reuse. What's to stop the user from changing the ...
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7answers
864 views

How can I prevent users from using bad passwords in my web application?

There is a long discussion on whether it's the responsibility of the user or the system administrator to deal with the strength of the password. Obviously, the password is a very private thing, but ...
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How to easily remember lots of different passwords?

I know that you shouldn’t use the same password on every site. But, when you log into several dozen sites, keeping track of all the passwords can be pretty hard. What system do you recommend that ...
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4answers
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Is forcing users to change passwords useful?

In many places, there's a policy that force the user changing it's password once a few months. The logic here is, that even if the password have leaked somehow, it'll be abused only for a relatively ...
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2answers
565 views

Banning specific passwords?

There have been a couple of questions about enforcing good passwords, so I thought I'd add my own: In addition to enforcing a minimum Shannon entropy, would it generally be a good practice to ...
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password complexity policy for non “English” passwords

In an internationalized application, what is the best practice for a policy on complexity of passwords? I am not having luck searching for the answer. Wikipedia lists these items for password ...
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2answers
358 views

Is it a security risk to remind users of the password requirements at login?

I regularly find myself trying to login to websites where I don't remember the password I use. I make some guesses as to what I might have used but usually wind up having to reset it. One thing that ...
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3answers
868 views

Do you think it's a good policy to disclose your password encryption method to users? [closed]

Do you think it’s a good idea to disclose your password encryption policies in your privacy policy or terms of service agreement? In other words, would you tell your users - and the world - you don’t ...
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633 views

Are we concentrating too much on password complexity?

As a developer and/or user, do I really need to worry about password strength if the system does not allow brute force attack to be feasible (implements a delay or attempt counter) or implements a ...
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633 views

Is it a good idea to have a “master” password?

Though I do have a good memory of passwords, it is quite impossible to have one password per application. Yet, it should be... My current way to deal with passwords is to have five passwords and to ...
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3answers
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How often should I reset my salt?

I'm thinking of implementing a salt recycling scheme on my user credentials database. The motivation behind this decision is that even if the attacker manages to get his hands on the database and has ...
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6answers
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Does having a minimum number of digits improve password security?

Some password systems will enforce at least X of a type of character - a common one I see is 'minimum 3 numeric characters'. As far as I understand, simply allowing certain character classes, like ...
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3answers
640 views

An alternative to traditional passwords: is there some merit to this idea?

If you've got a website aimed at people that are not neccessarily technically proficient, letting new users choose their own password isn't very secure because of the simple fact that a lot of people ...
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2answers
492 views

What does “Change your password everywhere else” e-mail from compromised service mean?

I've recieved an e-mail from ubuntuforums.org a couple of hours ago: [...] the attacker has gained access to read your username, email address and an encrypted copy of your password from the forum ...
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3answers
386 views

Does prompting for security questions on new computers add any security on banking websites?

When you sign into Bank of America on a computer you haven't used with them before, the site prompts you to answer one of your security questions. How exactly does this make the site more secure? ...
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3answers
560 views

Does it make any sense to alter a hashed password? [duplicate]

I've always wondered if it would make any sense to put fake characters into a hashed password? For example this is my password: 1234 and after hashing the password , this is the result: abcd Then ...
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4answers
2k views

Send new password by email is bad practice but what to do if user forgot his password?

According to http://plaintextoffenders.com/post/7006690494/whats-so-wrong-about-sending-a-new-password-in it's bad so what to do ? Just ask him to set a new one ?
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3answers
323 views

How secure is this method to remember security questions?

So I found an interesting method of remembering those pesky security questions. Basically, the guy takes a hash of the question (IE what is your mother's maiden name?) and then appends his own ...
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3answers
1k views

Where did common “minimum password length” guidelines originate?

Not long ago, the common wisdom was that passwords should be at least 8 characters long. These days, the most common minimum is 12. Where did these common values originate? Interestingly, 8 is ...
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3answers
540 views

Use of rainbow tables with the NY Times hack?

The NY Times recently published a story about how they were hacked during a four month period. The hacks allegedly were carried out by part of the Chinese military. One part of the story that ...
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2answers
416 views

How to refute “don't use internet if you don't like it” answer?

I hope it is legit question, similar to, for example, Why do law-abiding citizens need strong security?, et al. and it is tightly conected with user's security, privacy, etc. The response I always ...
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2answers
349 views

Does a random set of secondary passwords add any security?

My bank uses this rather uncommon policy of authentication. They of course have a password, which has quite strong password patterns like "use alphanumeric characters and symbols, 8+ characters" are ...
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4answers
341 views

Is there any risk in allowing more more failed login attempts before autobanning for a longer time?

By default most software seems to have rather low "burst" settings, like 3 to 5 login attempts before a temporary autoban for a couple minutes. Especially banks have a very low limit before access is ...
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2answers
1k views

How often should passwords change?

I'm asking two very related questions As an admin what policies should be enforced regarding the frequency of password changing? I have an idea that users should be forced to change their ...
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2answers
234 views

What are the weaknesses of my authentication scheme?

So, recently, after going through some infosec training (FutureLearn's Introduction to Cyber Security, which I heavily recommend as well-explained newbie material), I decided to take the plunge and ...
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1answer
61 views

Unique Touchscreen Authentication Schemes

I am working on a new software application that will have access to millions of patient medical records. I want this to be secure. The initial thought process was to simply use a standard username ...
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4answers
714 views

Insecure to require numbers in passwords?

Earlier, I went to a site that required a number and special character, and it got me thinking – wouldn't that make the password easier to brute force? If you assume most passwords have around 12 ...
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5answers
217 views

How many combinations does a specific password policy allow?

Recently I was arguing about password policies. Assume you have a policy which requires 10 characters and additionally at least one letter, one number and one special character. My companion was ...
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5answers
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Password reset links: random value or authenticated message?

Which is better? Create tamper-proof encrypted password reset token which contains the user id and the expiration time within the encrypted token. Generate a random token and store it in the ...
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7answers
4k views

Pronounceable Password Generator

I am currently looking for a password generator which produces pronounceable passwords. I have used this random password generator a few years ago to generate a 42 characters long password and found ...
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4answers
256 views

how to check for duplicate passwords

Is it possible to check if like 100 people are using the same pasword? without risking anyones password getting out? I heard google does this, not allowing the user to set a password 1000 people are ...
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2answers
350 views

Including and storing the order of character entry in a password as an enhanced security measure

I'm sure I will be quickly corrected if this is a stupid idea, or if it has already been tried. My question is: has this idea been tried before? If not, are there good reasons it would not work, or ...
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2answers
112 views

Should password recommendations be different for devices, networks, and internet?

I started using a password manager last year and updated nearly all of my internet accounts to super-strong, unique passwords, and that isn't a problem, cause I only access them from web browsers or ...
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3answers
1k views

Is Username/Display Name Login more secure than email login?

I recently started playing Star Wars: The Old Republic, which for those of you who don't know, is an MMO. Before playing the game, I would always log in with my email/password combo. However, I got an ...
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646 views

Is it ok for software to store passwords locally in plain-text?

There are already plenty of questions about what to do when websites store plain-text passwords. But this one is a little different. I use a piece of open-source (see below) software for playing ...
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2answers
260 views

Is there a site like plaintextoffenders.com that shames companies that force insecure passwords?

I recently came across http://plaintextoffenders.com/ and I liked the idea. I wondered if there was a similar site that shames websites that force insecure passwords? I personally have a list of a ...
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2answers
318 views

How to prove a password guessing theory from Matt Bishop's book “Introduction to Computer Security”

First, this is not a homework problem. This is a problem from Matt Bishop's book "Introduction to Computer Security" which was used as one of the textbooks for a Computer Security class I took last ...
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3answers
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Why do some websites force users to come up with difficult passwords?

I can't understand why we commonly force users to come up with difficult to remember passwords. * Your password must contain at least one number, one uppercase character, and one special ...
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1answer
243 views

Computer team's password change time different from other users?

We need to determine a password policy for our organization. All users, in general, will have 90 days until they will have to change their passwords, complexity required and passwords need to be at ...
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1answer
69 views

Forgot Username/Email - Do extra credentials equal enough to log the user in?

I am working with another UX guy and he's let me know that there have been some studies surrounding the fact that when a person goes through a "forgot username/email" process, they enter in extra ...
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3answers
320 views

What implementations are possible for dual control?

An organization requires employees to use 2 person authentication in some scenarios. That is, when accessing, say, a server, secret knowledge from 2 people should be used for authentication. No one ...
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1answer
106 views

Protecting SSH service with many inexperienced users

One of the universities I know has a rather unique password policy. They issue shell accounts to all computing students with strong passwords that are unchangeable. It is done via the passwd -n flag ...
4
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2answers
307 views

Password strength metrics

In the question Source code as password I suggested using a combination of entropy and as @Lawtonfogle put it 'meatspace difficulty'. As suggested in the xkcd comic correct staple horse battery is a ...
4
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3answers
248 views

Why is password strength often underestimated and uncertain in the context of password hashing?

An aspect of security has bugged me for a long time: Why is there positive certainty about the importance of hashing algorithms and salts, but password strength is either never mentioned at all or ...
4
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2answers
196 views

Guidance for “image based” password reset challenge

Thycotic has a Password Reset Server that allows the user to select from several images. What general guidance is there for an image-based password reset challenge question? Examples may include ...
4
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2answers
896 views

Would a massive blacklist of guessable passwords be useful? [duplicate]

Suggestions to make a good password all focus on creating a string that a computer (or more likely, a network of computers with multiple GPUs) can not guess. Putting a password meter for when users ...
4
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1answer
326 views

How does the mobile security technology APNS and 3LM work?

APNS is an iPhone technology that assists with mobile push. 3LM is a BIOS-level security technology embedded in certain Android phones. I recently got off the phone with Boxtone and they said they ...
3
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7answers
3k views

Is it possible to detect password length from hash? Does doubling your password add more security?

Assuming a service doesn't store a plain text password, am I right in saying that the answer to this question depends on the service? On a bad service, the hash length is related to the password ...
3
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4answers
550 views

Is there any explanation (other than storing plaintext) for case-insensitive passwords?

I've come across a few organisations stating that passwords are case-insensitive. Obviously this is ridiculous, and a gigantic red flag from a security point of view. Is there any explanation for why ...
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4answers
629 views

How to tell if a site is securely storing passwords? [closed]

A site I frequent has a policy to make you change your password every 90 days. That's a cool policy, but I stumbled upon an old xkcd and facepalmed myself, because lots of doxing happens on this site. ...