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

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Are password complexity rules counterproductive?

In creating a login for this site I chose a nondictionary password that would be extremely hard to guess, but easy to remember. I was told that it did not meet complexity rules. After several ...
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5answers
588 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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3answers
3k views

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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5answers
2k views

Is Skype secure enough to transmit passwords?

Is it considered "secure" to send a password in a skype message and delete the message after the recipient remembered the password?
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3answers
762 views

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
775 views

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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2answers
1k views

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
893 views

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
959 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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6answers
7k views

Are services like “LastPass” less secure, as they have all my passwords protected by a single password?

If the LastPass service has all my passwords and someone gets access to my LastPass password, this person will have access to all my passwords. Isn't that bad for security?
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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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How secure is NOPASSWD in passwordless sudo mode?

On all our boxes we have ssh access via keys. All keys are password protected. At this moment the sudo mode is not passwordless. Because the number of VMs are growing in our setup, we investigate the ...
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5answers
787 views

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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6answers
597 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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1answer
555 views

XKCD #936: under what assumptions is 1000 guesses/second over a network plausible?

In XKCD #936, a rate of 1000 password guesses/second is proposed as a "plausible attack on a weak remote web service". Under what assumptions is this rate plausible? It seems much too high to me. I ...
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3answers
809 views

How much information about the reason for an unsuccessful login should a web application give?

After an unsuccessful login attempt, should I inform the user about its reason? Or more generally, how much information about the reason for an unsuccessful login attempt should a web application ...
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3answers
11k views

Is a password protected PDF file safe for bank statement attachments?

My bank emails my monthly statement to me in a password protected PDF attachment. Is this a secure method of transmitting something as sensitive as bank statement?
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1answer
445 views

Is the Litecoin Scrypt hashing technique a threat to hashed passwords?

The Bitcoin alternative, Litecoin uses a different algorithm to protect the block chain, namely Scrypt (not Sha256). Given that GPU accelerators exists, and ASICS are due to be released, does the ...
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4answers
2k views

How secure is the SRP that Blizzard uses to protect passwords?

Blizzard very recently announced that their network was compromised, but they assure users in their statement that the password information that the attackers had access to was saved in a secure way: ...
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7answers
837 views

Aren't password managers still incredibly risky?

I understand the utility in having one application remember a bunch of long, randomized passwords, but all you'd need is one well-placed phishing scam or a keylogger and they get all the keys to the ...
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1answer
411 views

“Please Enter Nth Character” without HSM

This question has been asked a few times, but always in the format "How does examplewebsite.com implement their 'please enter xth yth and zth characters of your password' function?" And the ...
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2answers
944 views

Can a Firefox add-on or plug-in access the user's websites' saved passwords in decrypted mode?

Going deeper into the previous question on Firefox plugins and add-ons malware risks: Could a Firefox add-on potentially decode and capture the encrypted websites' passwords saved in the browser?
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3answers
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Additional security of keyfile on top of a master password for KeePass

I use KeePass + Dropbox to manage and synchronize my passwords across my devices. This system works really great and I trust KeePass' security model. However my biggest remaining concern is the ...
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4answers
492 views

What is the best way to hand out passwords to a widely spread diverse employee base?

I have a problem I need to solve - specifically, how to hand out passwords to people in a variety of locations, and with a wide variety of access. I've thought of some options, but there 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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9answers
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Why do we authenticate by prompting a user to enter both username and password? Does prompting the password only suffice?

I don't know why do we authenticate by prompting the user to enter both username and password. In my mental model, prompting password only suffices. The reason is as follows: Assume there are x ...
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8answers
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What chars should I not allow in passwords?

I am planning to develop a website that require that the users register a username and a password. When I let the user choose a password, what chars should I allow the users to have in the password? ...
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5answers
767 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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4answers
1k views

Does the strength of password matter in bcrypt?

Even if I choose 1 character for my password or 32 characters with numbers, letters, uppercase symbols etc. the bcrypted password will still be 60 characters length password. So does the password ...
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2answers
4k views

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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5answers
728 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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5answers
6k views

How can I avoid putting the database password in a perl script?

I have a cronned perl script that connects to our database and does various kinds of lookups and integrity checks. The original script was written by someone long ago. My job is to make some changes ...
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3answers
458 views

has scrypt withstood the test of time?

I've always heard that scrypt was better than bcrpyt... because of memory causing GPU a very difficult time to crack. However, the notion always was that scrypt hadn't been tested, it was kind of a ...
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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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4answers
854 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

Is a password in the clipboard vulnerable to attacks?

I see situations where you may have to input the same password more than once. You may type it in a text editor and copy it to clipboard, to paste it two or more times. In what scenarios this could ...
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7answers
2k views

Does adding dictionary words to passwords weaken them?

This might sound like a stupid question, but hear me out. If I'm encrypting my financial information and sensitive data via a program like TrueCrypt, the strength of the password is going to matter a ...
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3answers
1k views

Cryptographic Security of Dynamically Generated, Non-Random Salts

So when it comes to security, when I have an idea that seems good, but no one else seems to be doing, I try to assume that I'm overlooking something obvious or otherwise significant. This is one such ...
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2answers
335 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
367 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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2answers
600 views

Password generation - too primitive?

A while ago (12 years old), I recognized my passwords weren't safe at all. Because I used the very same password everywhere, some grumpy admin could easily take over all my accounts (he got mail and ...
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3answers
390 views

If multi factor authentication is enabled, how should that affect self-service password reset?

Given that security is only as secure as its weakest link, suppose I have website with additional authentication enabled in any of these ways: (example, multiple conditions may be required) ...
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3answers
301 views

Is there any conceivable reason to prevent a password change in an authentication system?

I connect to the VPN of another company with a company-specific username and password (they aren't giving everyone the same password to every company to access it or anything ridiculous like that.) ...
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2answers
1k views

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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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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1answer
285 views

Is this cross-site password model secure?

I'm looking for a way of securely having passwords for different pages. Say I generate this password: ild23rfsfdfg%*#fArg34t34657%537@asd7oak2094^*q2k2k@Kk3j4tn453Q5# Then, for each site, I change ...
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3answers
567 views

How can I promote good password practices in an organization that doesn't currently care about that?

I work with an organization that uses some very poor practices such as using default user accounts, default passwords (or passwords the same as user accounts), sharing password information between ...
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3answers
307 views

How to test if a browser add-on is safe

I came across this plug-in that started some alarm bells ringing. The add-on would help submit a website to web directories. The first 100 submissions are free, then you need to pay $20 via pay-pal ...
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2answers
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Bypassing the BIOS password

Are there any reliable methods that allow an attacker to bypass a BIOS password, or alter BIOS settings without entering the password? A few ideas come to mind: The old battery trick (remove ...
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3answers
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HMAC Based Request Signing - Storing the Salt

I'm working on a (non high security) project that currently isn't live but might go live at some point. We have a REST API (implemented using Restlet and Neo4j) running on a server and an Android ...