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

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65
votes
12answers
10k views

Do we really need a long and complicated password for websites?

Most of websites that handle important information (Gmail, for instance) have some kind of brute force protection. Sometimes if you try more than X times it will lock the account or at least give you ...
64
votes
4answers
8k views

Does Microsoft's “Password Ban” list insecurely store user passwords?

Supposedly, Microsoft is banning common passwords, and their list will dynamically update: Microsoft says it is dynamically banning common passwords from Microsoft Account and Azure AD system. [&...
64
votes
13answers
9k views

Should I allow browsers to remember my passwords and synchronize them?

I wonder, how wise is it to allow Chrome and Firefox to a) remember the passwords b) synchronize them? My gut tells me that if it's not man in the middle who can intercept them, but Google and Mozilla ...
64
votes
21answers
17k views

How can I avoid my password being harvested by key loggers from internet cafes?

During traveling, especially in poor countries, sometimes you are going to need to use the internet at an internet cafe and you really can't be sure whether anyone has installed anything to listen to ...
64
votes
8answers
7k views

Is forcing users to use a strong password effective?

I am designing a service that would, among other things, store sensitive information. To ensure no unauthorized access of this information, it would be encrypted with a key derived from their password ...
64
votes
12answers
14k views

What to do about websites that store plain text passwords

I recently received an email from a popular graduate job web site (prospects.ac.uk) that I haven't used in a while suggesting I use a new feature. It contained both my username and password in plain ...
63
votes
9answers
11k views

I almost searched my password, but didn't press enter. Is my password at risk, because of autocomplete or anything else?

Without even thinking about it, I typed my password into the Google search bar, but I didn't press enter. Since autocomplete is on, does that mean my password has been logged or indexed somewhere? ...
62
votes
5answers
5k views

Do 2FA sites leak info by confirming a correct password guess?

Here's my relatively layman's view of the issue. Many websites tout multifactor authentication (MFA) as an enormous boost to the security of users' accounts, and it can be if implemented properly. ...
62
votes
8answers
7k views

Is it OK to tell your password to your company's sysadmin?

I'm working in a small company (20 employees) as a senior software engineer. After having problems with my email, our newly employed IT administrator asked me to write my user password to someone in ...
62
votes
12answers
12k views

How reliable is a password strength checker?

I've tested the tool from Microsoft available here which tests password strength and rates them. For a password such as "i am going to have lunch tonight", the tool rates it's strength as "BEST" and ...
61
votes
10answers
18k views

Bad practice to have a “god” password?

Is it bad security practice to have a password that will allow you to access any user account on a website for support purposes? The password would be stored in a secure manner and would be super ...
59
votes
8answers
11k views

Is password reuse a problem if the password is very strong?

I always read that using the same password on multiple sites is a risk. I'm wondering what is the real reason for this? In my case, I use the same password on multiple sites everywhere. My password ...
59
votes
9answers
17k views

Generic error message for wrong password or username - is this really helpful?

It is really common (and I would say it is some kind of security basic) to not show on the login page if the username or the password was wrong when a user tries to log in. One should show a generic ...
57
votes
11answers
46k views

Are password-protected ZIP files secure?

Following my answer. If I can list contents of a password-protected ZIP file, check the file types of each stored file and even replace it with another one, without actually knowing the password, then ...
56
votes
12answers
4k views

How do you log in from an unsecured computer?

Suppose that you are on a cybercafe, at a friend's home or at your work office, and you need to log in on a site, but you feel that the the computer can not be trusted (e.g. your friend isn't tech-...
55
votes
5answers
19k views

Is sending passwords through cellphone text messages secure?

Both the sender and the receiver deleted the text after it was sent, but is it still possible that it exists somewhere and that someone can get to it?
54
votes
2answers
7k views

What should end-users do about Heartbleed?

What should one do about the Heartbleed OpenSSL exploit? mainly talks about what people running websites should do about Heartbleed. What should end-users of websites be doing? Do they need to ...
51
votes
4answers
5k views

Why submit a website to plaintext offenders?

I've read this question and to quote from the accepted answer Besides that, by submitting the site to plaintext offenders, you will provide a third-party point of view, which might help your case....
51
votes
8answers
4k views

I'm an IT consultant. Should I discourage a client from telling me his password?

I'm an IT consultant. One client has known me for a few years. He wants me to do some work on his kids' laptop again. I'll need to log into his kids' Windows user account. (I'm guessing that multiple ...
51
votes
5answers
11k views

Are GUIDs safe for one-time tokens?

I see a lot of sites use GUIDs for password resets, unsubscribe requests and other forms of unique identification. Presumably they are appealing because they are easy to generate, unique, non-...
51
votes
1answer
3k views

What's the risk if I accidently type my password into a username field (Windows logon)?

I'm used to logging into my personal Mac which is a password-only field (like waking from sleep mode). Sometimes I have to use a Windows network on which I have an account, but of course I have to ...
50
votes
10answers
12k views

Why does the user pick the password?

Almost every web service I can imagine has the user pick the password. Why is this? Couldn't the system choose a better password? It doesn't have to be some complicated mess; see http://security....
50
votes
6answers
8k views

How do some sites (e.g. online banks) only ask for specific characters from a password without storing it as plaintext?

I thought How can a system enforce a minimum number of changed characters... would answer my question, but it seems this is a different case. When I sign on to my online banking account, I'm prompted ...
49
votes
38answers
9k views

What is your way to create good passwords that can actually be remembered?

What are the methodologies which can be used to generate "human" good quality password? They have to ensure a good strength and also easy to remember for a human being.
48
votes
5answers
9k views

How can I know that developers will be ethical and not record my password in plaintext

I am not asking why hashing should be done. Instead, I want to know how to prevent that developers record user passwords to hack their user's other accounts, especially their email. Couldn't they ...
48
votes
7answers
4k views

Is the option to jump to blanks in password fields a security risk?

Using Ctrl + ← / →, it's a common behavior across different operating systems to jump from word to word (or from blank to blank) in text input fields. Now I've discovered that this also applies on ...
48
votes
7answers
3k views

Do security questions subvert passwords?

Do security questions subvert hard to crack passwords? For example, if a site requires passwords with a certain scheme (length + required character sets) and has a security question, why would someone ...
47
votes
10answers
5k views

Isn't OAuth, OpenID, Facebook Connect, and others crazy from a security standpoint?

I work with APIs all the time and I work with web developers who insist that OAuth, OpenID, etc are far superior than a home-brew method. Every site seems to be using these as well now for ease of use ...
47
votes
9answers
6k views

Can users make use of a password manager when banks tell them never to write passwords down?

Consider a user who wants to use a password manager for their banking passwords. Advice from banks usually says they should never write down their password. The user would be concerned about going ...
47
votes
2answers
5k views

Pre-hash password before applying bcrypt to avoid restricting password length

Good practice is not to unnecessarily restrict password length, so that appropriately-long passphrases (perhaps 35-45 chars for 6/7 dicewords) can be used. (See e.g. Should I have a maximum password ...
46
votes
5answers
4k views

Is it safe to tell your users what kind of hashing algorithm you use?

For example, on the user registration page, is it safe to tell people "Your password will be stored as a one-way hash using the (whatever) algorithm."
46
votes
9answers
5k views

Why improvising your own Hash function out of existing hash functions is so bad

I'm afraid I'll have tomatoes thrown at me for asking this old question, but here goes. After reading that cooking up your own password hash out of existing hashing functions is dangerous over and ...
46
votes
3answers
9k views

Paypal sent an email addressing me with one of my old passwords as my name

I got this email from service@intl.paypal.com, with the title: Your account has been limited until we hear from you. I think this is a scam / spoof email because I don't see any notification in my ...
46
votes
9answers
18k views

How long should the password be?

The minimum password length recommended is about 8 characters, so is there any standard/recommended maximum length of the password?
45
votes
7answers
7k views

Do bad passwords produce bad salted hashes?

When you have a password stored in a database that has been strongly hashed and salted does it really matter if the underlying user password is weak? If you setup features like limiting login ...
44
votes
4answers
7k views

Is it good practice to ban an IP address if too many login attempts are made from it?

Since an IP address does not necessarily represent a specific device, but probably a whole network/company/etc. does it at all make sense to block an IP address if there is a significant amount of ...
43
votes
7answers
11k views

Why isn't open WiFi encrypted?

As far as I understand, WiFi networks that require no password send traffic through the air unencrypted. Those that require a password encrypt each connection uniquely, even if they're all using the ...
42
votes
13answers
13k views

Is it good practice to send passwords in separate emails, and why?

I have heard from different people and in different places that if I send an encrypted file to someone else, I should send them the password in a separate email; but why? If someone is sniffing, they ...
42
votes
4answers
3k views

Is using bcrypt on existing SHA1 hashes good enough when switching password implementation?

I'm working on improving a CMS where the current implementation of storing password is just sha1(password). I explained to my boss that doing it that way is incredibly insecure, and told him that we ...
41
votes
10answers
7k views

What type of pattern should I use for my passwords?

I have a lot of accounts and until some time ago I used an universal password for all of them. Right now I have a different password for every account depending on the website name that I am logging ...
41
votes
7answers
5k views

Are partially typed passwords a potential security risk?

I just sat down at my work computer and began to unlock it by typing in my password, I got 6 of the 8 characters in and decided I wanted coffee and walked away to get it. I came back, realized I left ...
41
votes
6answers
17k views

https security - should password be hashed server-side or client-side?

I am building a web application which requires users to login. All communication goes through https. I am using bcrypt to hash passwords. I am facing a dilemma - I used to think it is safer to make a ...
41
votes
7answers
34k views

Is saving passwords in Chrome as safe as using LastPass if you leave it signed in?

Justin Schuh defended Google's reasoning in the wake of this post detailing the "discovery" (sic) that passwords saved in the Chrome password manager can be viewed in plaintext. Let me just directly ...
41
votes
3answers
4k views

Security Review - password_hash implementation for PHP

I'm currently working on a "helper function" for PHP's core to make password hashing more secure and easier for the majority of developers. Basically, the goal is to make it so easy, that it's harder ...
40
votes
7answers
13k views

Somebody hacked my router and changed my wifi SSID

One of my neighbours hacked the password of my router and he uses my limited internet package. I change the wifi SSID almost daily, but he can hack it easily. Today, he changed the SSID to a hate ...
40
votes
7answers
3k views

“Real” Salt and “Fake” Salt

During a Q&A period at DEFCON this year, one member of the audience mentioned that we're using "fake salt" when concatenating a random value and a password before hashing. He defined "real salt" ...
39
votes
2answers
14k views

I just send username and password over https. Is this ok?

When a user's logging in to my site, they send their username and password to me over https. Besides the ssl, there's no special obfuscation of the password - it lives in memory in the browser in the ...
39
votes
10answers
4k views

Is there a method of generating site-specific passwords which can be executed in my own head?

I was thinking recently about password security. My goal is to have mostly random passwords, that are different for each site. But you also should be able to remember them (or re-generate them) ...
38
votes
10answers
5k views

Is there any point in using 'strong' passwords?

Let's say I'm setting up a new account on a website. Should I bother using a strong password? My reasoning is this: Password strength is a rough measure of how long it would take to brute-force my ...
38
votes
9answers
27k views

Feeding /dev/random entropy pool?

Which way of additionally feeding /dev/random entropy pool would you suggest for producing random passwords? Or, is there maybe a better way to locally create fully random passwords?