Specific to the security of passwords: hashing, entropy, cracking, resets, lockouts, etc.

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Does an *additional* company-wide password offer any real security?

So, let's say a company has what could be referred to as an "access key". Each user has their own username and password, and there is an additional company-wide access key that people must input with ...
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7answers
2k views

Why don't we reward users who choose strong passwords? [closed]

Suppose there is a web property that has some sort of reward system or commodity that its users desire. It could be reputation on Stack Exchange-like sites, rank badges on message boards, or add-on ...
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5answers
8k views

How do online accounts get hacked?

How does your typical users run-of-the-mill Facebook/twitter/gmail/AIM/etc account get hacked? Is it simply a matter of a weak password? Are they typically the victim of phishing or other social ...
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5answers
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How can I help catch an email scammer who is contacting me?

My friend's GMail account was recently hacked and the perpetrator sent out one of those classic "help I was mugged, I need money" style e-mails. (Edit: I know it's legit; my friend called me to tell ...
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4answers
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Handling passwords in a web application

I am trying to learn how a secure web application is developed. Particularly, I am unsure of how passwords are sent from the client to the server. For a typical user/password login form. If the client ...
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2answers
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What is the purpose of a Pepper?

I've been trying to find out exactly what a pepper is. The only things I could accurately determine are that a Pepper: Is theoretically unique from site to site and hard-coded in the site's source ...
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3answers
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How can I prevent someone from accessing a Windows XP system via boot disk?

Apparently a computer system protected by a a login password, e.g. Windows XP, can be easily hacked by someone with physical access to it using methods like this one: ...
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4answers
2k views

Why use random salts?

I read this blogpost on how to store passwords in a database, the secure way. Elbert tells us to do this: Generate a random salt and include something random and the username in it. Hash this. Hash ...
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2answers
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How secure is asking for specific characters of passwords instead of the entire thing?

In some password-authenticated sites, you are asked to enter a random selection of specific characters from your password rather than the whole word/phrase. For example, it might say 'Enter the 1st, ...
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5answers
887 views

Should passwords be truly random?

When generating a password, should it be "truly random" or should I make it a little less random by enforcing some rules? If a password is generated at random, it could come out all-lowercase letters ...
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8answers
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Facebook account keeps getting hacked, can't seem to figure out why or how?

One of my friends, she has a lot of friends on Facebook, and uses it for marketing. Her account keeps getting broken into. Her password gets reset and/or gets locked for changing resetting password ...
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3answers
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With ASIC bitcoin miners, should SHA256 be considered insecure for password hashing?

I'm sure everyone here has seen the rise and further rise of bitcoin. The process used for mining bitcoin is basically "let's brute force an SHA256 hash that is less than this amount" That being ...
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5answers
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If a bank says they do not have my login and password info, is that true? [closed]

After an investigation on their part, the bank simply states that if someone accessed my accounts via internet banking, (and a simswap) I was the one who didn't secure my login and password info. I ...
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2answers
1k views

Is there any advantage of bcrypt over multiple iterations of SHA-x/MD5?

I know that a good password hashing algorithm should be slow. MD5, SHA256, etc. are fast. So I've been adding multiple iterations of SHA-256 hashing to my web apps (around 50000). Getting the hash of ...
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4answers
1k views

Forgetting passwords typed in too frequently

It has happened to me several times that I've become so used to typing in a password I can't consciously remember it and it's purely muscle memory. This is particularly true with complex passwords ...
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3answers
2k views

What is the risk and mitigation of accidentally typing a YubiKey password in an open forum?

I have a YubiKey in my laptop (for testing) and accidentally broadcast my YubiKey password out to the Internet. Since this is only a test key, and has no access to anything of value, here are some ...
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3answers
6k views

Is LastPass' locally stored One-Time-Password recovery a security problem?

If you forget your LastPass master password then LastPass provides the possibility to recover access to your vault using a One-Time-Password (OTP) which is stored locally but is initially disabled. ...
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1answer
3k views

How will security need to be changed if P=NP?

If we suppose that it is found that P=NP, how will security measures need to be changed? I'd like to know the major security measures that are affected, and how they would need to be changed. We can ...
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4answers
1k views

MS-SQL Password Storage

What would be your recommendation for replacement of an MD5 hash approach to password storage within an MS-SQL database be?
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2answers
779 views

Zip file with two password

I used this command to password protect a zip file on Linux : zip -P 9000 hash.zip hash.py and it creates the zip file just fine, then I wrote a program to test every possible password on it from 1 ...
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2answers
4k views

Estimating the size of a rainbow table

What are rainbow tables and how are they used? Gives a very precise answer about what rainbow tables are and how they are used. I had always confused hash-tables and rainbow tables. My question is ...
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1answer
1k views

Is Rfc2898DeriveBytes using HMAC SHA1 still considered “secure enough” for hashing passwords?

I've been told by a CISSP that the .NET class Rfc2898DeriveBytes would not pass a security audit today because it still uses SHA1. It's reliance on SHA1 - even with the iterations - leaves it too ...
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3answers
590 views

Is it inconsistent to tell users to “not click on password links in email”, and requiring clicks on “forgot password” links?

On one hand, IT Security shops have been telling users to not click on links in email because they can do damage to your computer, or phish your personal information. Many of those issues are ...
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4answers
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Authenticating without a database

I've been inspired by a question over on Code Review, which boils down to: What is the proper way to authenticate a user without a database? Would it be the exact same process if you stored ...
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4answers
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Why will Google no longer allow me to end or begin passwords with a space? [closed]

Why won't Google allow me to use a password ending in a space anymore? Backstory: I have memorized a cipher that allows me to generate a different and very strong password across many different ...
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5answers
792 views

Altering passwords before storing

Assume that I'm using bcrypt with a unique salt (or some other best practice) to hash user passwords before storing them in my database. Is there any security advantage to be gained by ...
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6answers
36k views

Is howsecureismypassword.net safe to use?

Is it safe to enter my real passwords to test them? I mean, are the entered passwords being recorded/transmitted to someone else?
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6answers
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Is it useful to protect hashed password with encryption?

Imagine that I am hashing the users' passwords with a random, long enough, salt, using key stretching, and a secure hash. Would it be more secure to finally encrypt the hash with a symmetric key?
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5answers
780 views

Security of using passwords or even passphrases to encrypt files

Is it ever appropriate to use real-world passwords to encrypt files to be sent via unsecure means. By real world, I mean a password that is memorable and memorisable by a mere person? I am implying ...
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5answers
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Passwords - any statistics on user behavior?

I'm looking for analyses of how users choose and use passwords. I'm sure there are many resources out there that analyze user passwords. For instance, I've seen many people analyze dumps of password ...
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2answers
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Is it safe to store the password hash in a cookie and use it for “remember-me” login?

I want to store an encrypted string of the password hash in a cookie and use the hash to lookup the user and log them in (if they want to be remembered). Is this safe? The password is one-way hashed ...
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3answers
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Does the salt need to be unique or not predictable?

I always thought that salts is simply used to prevent rainbow tables to be used. Other have suggest they should be unique on a per account basis. Currently i have been using a config file to use as ...
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3answers
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Do users of non-latin character languages suffer from spyware and trojans?

Do Chinese, Japanese, other languages that can't be represented in ASCII get their passwords stolen? I figure there can't be some sort of bruteforce attack software for them, right? Their characters ...
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5answers
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Are case-insensitive passwords a bad idea?

I recently discovered a service where the password was not case sensitive. I understand basic principles of encryption and hashing so I am a bit worried, is this service storing my password in plain ...
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4answers
7k views

HTTP Basic auth password storage more secure than Digest auth

If you are using SSL already, it appears Basic auth is the way to go since you can perform bcrypt with the password when you store it in the database, where as Digest auth only allows md5. As we know, ...
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2answers
1k views

Requiring regular password change but storing previous paswords?

My bank requires me to change my password regularly but then they can detect if my password was used before. They probably store the old password (possibly hashed) in order to detect it. I think this ...
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8answers
267 views

How to choose a password that I have to remember for a long time but do not use a lot

I have a scenario where I have to remember a password / keyphrase, which I will not be able to recover if I forget it, for a long time (probably more than 10 years). The problem is because this ...
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5answers
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Is it worth the effort to store FTP passwords encrypted?

I have a project to build a system that needs to push files to multiple third-party FTP servers. I have asked these third parties to provide a more secure interface; all have declined. So now I have ...
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4answers
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Does it indicate a bad password system to disallow certain characters in passwords?

When creating an account to the game League of Legends, the user's password must comply to a few rules. The one I'm concerned about is the "Must not contain slashes or spaces" one. The others are ...
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3answers
644 views

Security of pronounceable passwords

Some random password generators support the generation of pronounceable words of any given length n. Assuming that words are derived using 26 lowercase letters, the number of possible words of length ...
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4answers
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How dangerous is it to store password in plain text on sites like GitHub?

I have a few private repositories set up on GitHub for some of the projects I am working on for my company. These applications connect to databases and I have database authentication credentials ...
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2answers
383 views

How much security is compromised if we accept other characters as login (other than the original password)?

I've just realised that facebook accepts 3 forms of a password: Source: Facebook actually accepts three forms of your password: Your original password. Your original password with the ...
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2answers
429 views

What problems does this “recover account” procedure have?

On a website I run I have implemented this procedure for account recovery (forgotten password procedure). I would like to know whether there are any issues with it that I have not spotted, that make ...
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5answers
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Is there any good reason not to salt/hash passwords you store?

Two organisations I frequently deal with (including my bank) ask me my password to authenticate myself with them... well... they ask for "random" characters from my password. As I understand it, this ...
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3answers
997 views

Calculating how secure my password is

I generally use GnuPG for encrypting my files and as far as I know its strength ultimately depends on the passphrase I use. So, I would like to know: how can I mathematically calculate how secure my ...
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4answers
716 views

How should I tell an organisation that they are vulnerable when I wasn't given permission to check?

I was recently at a village hall (in the UK), some distance from where I live, for a party. I noticed that they had unsecured wi-fi with an SSID of NETGEAR. I assumed it was free wi-fi for users of ...
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4answers
844 views

Should I obfuscate passwords before hashing? Should I pre-hash them on the client? What about salts?

For fun, and in my spare time I'm creating a simple CMS for my own purposes (with hopes to release for wider use... later), using PHP. I'm currently working on the login scheme now, and have a few ...
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6answers
792 views

Security of carrying passwords on person

While in college I decided to have a randomly generated 16 character password. I used parts of that password in various sites. However, one of the sites was compromised so I had to change my password. ...
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2answers
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Password auditing

Most password policies require the password to be at least 8 characters long and contain symbols from at least 3 classes (lower case letters, upper case letters, numbers, other). Problem is, that a ...
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3answers
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Should an admin user be able to edit passwords?

For your typical web app, should an admin superuser have the right to edit a user's password, or should only that user have the right? (Even with edit ability, the admin would never see the current ...