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

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Does a maximum length of password mean non-hashed storage?

When a system requires a password between say 6 and 20 characters in length, does it mean the password is stored without using a hashing function, and that the mysql-field (or similar) is 20 ...
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5answers
672 views

What concrete parameters can I change to make my passphrase-protected private gpg key more secure

There are several questions which discuss the resistance of passphrase-protected private gpg keys against brute force attacks. It seems, this kind of discussion could go on forever. Rather than ...
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7answers
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Taking password letters not whole one, is this secure? [duplicate]

I found a site which is taking password letters from their users not the whole password. Is this secure? Or do they have saved password as salted hash (MD5)?
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7answers
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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
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What are the differences between an encryption seed and salt?

Today I had a hard time explaining the difference to a friend. I know seeds are used when generating "random" strings. And salts are used when providing different outcomes to a hash. What is a ...
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2answers
6k views

How Does A Random Salt Work? [duplicate]

I don't understand how using a random salt for hashing passwords can work. Perhaps random salt refers to something other than hashing passwords? Here is my thought process: The salt is used to add ...
17
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4answers
1k views

How to treat non-optional bad security questions?

Every once in a while I have to set up an account on a site that, while apparently at least not storing my password in plaintext, still force me to choose from a limited set of security questions that ...
17
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4answers
13k views

Is it possible to securely store passwords using reversible encryption?

Everyone says that you need to use a non-reversible hash when you store passwords so that even if your database is leaked, the passwords themselves are still safe. I'm wondering if there is anyway to ...
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5answers
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Is sending plaintext passwords to a SQL Server database a security risk?

I have a database which has stored procedures which take plaintext passwords. It hashes them and inserts them into the DB. If an attacker has access to the DB connection, it is possible to intercept ...
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2answers
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Facebook API : App Secret - possible misuse

I've recently find out that by simple quick look into compiled code of one of our applications, you can get both App ID (API Key) and App Secret for Facebook API I suppose that we should really keep ...
17
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2answers
595 views

Bank accepts different password to the one that I set

I'm not particularly well versed in IT security so please bear with me. I recently discovered that my bank's online system will accept passwords that consist of the correct password, and a string of ...
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6answers
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Managing website passwords for small team

I'm part of a small group of people who manage a website and the server it runs on. We have many accounts with third-party websites or services that multiple people on the team need to access. What is ...
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2answers
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Essential things to think about before outsourcing authentication with OpenID, OAuth, or SAML

It's clear there there is no consistent set of features among any of the popular authentication providers. Below is an attempt to aggregate the similarities and differences I've noticed, but I ...
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6answers
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Is my custom password hashing algorithm insecure?

For all of my hobby web projects, I have coded a login system that these projects share. There is no critical data in these projects, the only critical data could be reused passwords. So I try to hash ...
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3answers
7k views

Is it possible to get the salt if I have the hash and original password?

Is it possible to get the salt if I have the hash and original password? My gut feeling is no, but would it be impossible or will it just take very long?
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7answers
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My IP address (with a NAS) is targeted by a hacker. What to do? Should I be worried?

I've noticed, based on the logging of my NAS, that my IP address is targeted by a hacker. I already took action by automaticly ban the IP address permanently after five unsuccesful login attemps. ...
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5answers
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Is an 80 bit password good enough for all practical purposes?

I know that asking how many bits of entropy comprise a strong password is rather like asking the length of a piece of string. But assuming the NSA is not on to you, and that it is hardly worthwhile ...
16
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3answers
774 views

Is it OK to tell your password to an admin? [duplicate]

Possible Duplicate: From a security point : Is it OK to tell your password to an admin? I am working in a small company (20 employees) as a senior SW engineer. After having some email ...
16
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3answers
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openssl: recover key and IV by passphrase

A large amount of files were encrypted by openssl enc -aes-256-cbc -pass pass:MYPASSWORD Openssl should derive key+IV from passphrase. I'd like to know key+IV equivalent of that MYPASSWORD. Is ...
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11answers
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Best practice for password distribution

I am about to set up a new account on my Linux server for a user that lives in another state in the U.S. I can't think of a good way to get them this user their password. There must be a standard ...
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6answers
2k views

What does “random” mean in the context of password creation?

Disclaimer: as you will see from my question I'm a total outsider in this subject, just very curious. I was wondering how easy it would be to crack a password-protected RAR5 file, and I found many ...
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5answers
3k views

The AES Crypt implementation hashes a password 8192 times to generate the key. Is this necessary?

I'm considering encrypting some small files (hundreds of kb apiece) using the AES Crypt reference implementation. Looking at the source, it seems that the encryption key is derived from the IV and the ...
16
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3answers
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Is a HMAC-ed password is more secure than a bcrypt-ed or scrypt-ed password?

Given an option , which one should I choose , a HMAC for storing a password securely or a bcrypt or scrypt library?
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3answers
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Storing passwords in reversible form - a genuine use-case

What's wrong with you, you crazy fool, you're not supposed to be able to retrieve a password in plain text! I know. Hear me out. Assume I've got a service that's similar to Mint.com. For those that ...
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7answers
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How different should my passwords be? [duplicate]

Suppose I use remember one long high entropy master password, and use variations of it for each of my passwords. Eg if I remember tSaF4nWeACVkUU4 as a master password and use tSaF4nWeACVkUU4t (with a ...
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4answers
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Does two-factor authentication reduce the need for a long password?

I've recently enabled 2-factor auth on a number of web apps, mostly using Google Authenticator. Does this mean that the importance of a strong password on each site is reduced? I would prefer to use ...
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4answers
363 views

Are malicious relying parties able to abuse OpenID logins?

if I logon with OpenID into a website (crafted by attackers/hackers) I want to know how much damage can they do to me? Are they able to steal my contact info, name, etc (assuming I'm using Gmail ...
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2answers
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What's wrong with storing private keys in the cloud?

I know this sounds like a dumb question, but whats wrong with it? Assuming that all private data is encrypted (by the client) using PBE AES256, then is this scheme more vulerable than storing keys on ...
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4answers
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How are browser saved passwords vulnerable?

Most browsers offer to save the password after entering it on many logon pages. What types of vulnerabilities are there for such saved passwords. I'm interested in what ways malware on web pages ...
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2answers
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How secure is Keychain on OS X?

Keychain is a built-in app on OS X that stores all of the user credentials, and allows for one to keep encrypted notes in an easily accessible way. Does anyone know how secure Keychain is? I know ...
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7answers
850 views

To salt, or not to salt? [duplicate]

Possible Duplicate: Why is using salt more secure? Why would salt not have prevented LinkedIn passwords from getting cracked? Recently I decided that I wanted to learn more about web ...
15
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11answers
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Should I know my users passwords so I can check they can logon? [duplicate]

I have an issue with support for a system and I don't know what approach to take. It boils down to the question: Should I know my users passwords so that I can check with certainty that a ...
15
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3answers
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Is it a bad idea to add random characters to user ID and password?

I've heard people say again and again that you shouldn't implement your own security algorithm, and I'd like to ask you if I'm breaking this rule. I'm creating a traditional client-server application ...
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5answers
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Is it legal to log passwords from failed logins?

Is it legal to store/log mistyped passwords? How many of you have seen this happen in a log file or DB?
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2answers
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Password and Generated number - How does it work?

In my company, they don't allow accessing the company email or servers from outside the company network. To access the email from outside the network, you have to use: Username, password and a number ...
15
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5answers
69k views

How to generate dictionary for a dictionary attack?

I need to crack my own password. Advantage is that I know possible characters and maximum length. What I need is to create a dictionary. The dictionary should contain all the combos of characters ...
15
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7answers
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Password management/synchronization?

Is there a good enough service I could run on my own home (Linux) server that I could use for storing/accessing/synchronizing passwords so they could be available for me from multiple ...
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6answers
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Do salts have to be random, or just unique and unknown?

First of all, my motive is to avoid storing the salt in the database as plain text. As far as this question is concerned, the salt is not stored in the database. After discussion in comments and in ...
15
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7answers
367 views

Is a “security measure” that doesn't provide a security benefit actually harmful?

If a security measure is implemented that doesn't provide any additional security benefit, can it be considered harmful? As an example, consider a login page where the user is asked to enter their ...
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3answers
938 views

What can I do if my bank thinks my date of birth is “known only to me”?

My bank has recently replaced passwords with occasionally asking me information that is "known only to me". Such information includes my date of birth, postcode, and my mother’s maiden name. ...
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3answers
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Is HTTPS and Basic Authentication secure enough for banking webservices (RESTful)?

I have been reading about SSL/TLS for the last few days and looks like it has never been practically cracked. Given SSL/TLS is used for all communications between client application and the server, ...
15
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6answers
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Recommend Length for Wi-FI PSK?

I currently have a network set up with WPA2 and AES encryption, the password is 8 characters long but was randomly generated and contains no dictionary words. However I'm concerned about the ...
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2answers
1k views

How does varying character type increase strength of password?

When creating a new password, people often recommend you use both uppercase and lowercase characters, numbers, and symbols. How does adding any of these increase the strength of a password? There ...
15
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2answers
971 views

Distance between two passwords

It is known that people reuse their passwords across different sites. The reuse can be done in two ways: using exactly same password for two different sites, slight modifying the password of one ...
15
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1answer
928 views

Linux /etc/shadow password change security

I wonder what happens what happens when I am changing my password on a Linux system. Basically all passwords are stored in a file called /etc/shadow or /etc/master.passwd in BSD-like systems as I do ...
15
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2answers
1k views

Are there some good papers (or discussions) on using Markov chains or Hidden Markov Models for password auditing/cracking?

As a programmer and language enthusiast I've been very interested in Markov chains for some time. Considering the influence of natural language on password and passphrase selection (by humans of ...
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3answers
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Is it truly possible to store passwords securely, but be able to see the password?

Every place I looked, people recommended that storing passwords via encryption is like storing passwords in plain text. But every place I've looked, everyone recommends using a password manager like ...
15
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1answer
903 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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2answers
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Should password reset tokens be hashed when stored in a database?

Passwords are hashed so that if someone gains access to a database of passwords then they won't know what the actual passwords are and so they can't log in. If I can get a valid password reset token ...
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4answers
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SSH key auth, but still need password for sudo?

SSH with public-private key authentication comes enabled by default with most Linux distributions. This is great because when I create accounts for remote users I don't have to email them sensitive ...