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

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19
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4answers
4k views

Should I implement incorrect password delay in a website or a webservice?

With arguments expressed in this answer, there is a few seconds delay between user enters an incorrect password and when he/she actually learns, that password was incorrect. This security solution is ...
19
votes
5answers
1k views

Is it alright to tell everyone your encryption information?

I have an account in an online banking system and they have the FAQ with something like this: How secure is the <Online Banking System Name>? Each page you view and any information ...
19
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7answers
944 views

Are common passwords at particular risk?

The question Should we disallow common passwords like “password” and “12345”? on User Experience immediately made me think that these common passwords were extremely dangerous not because they are ...
19
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7answers
8k views

Are password reset links that don't expire a security risk?

I am currently working on a password reset flow. We have decided to go with a password reset link being emailed to the user's registered email and allowing them to follow that and input a new ...
19
votes
3answers
6k views

How secure is 7z encryption?

I have a text file in which I store all my bank details. I compress and encrypt it with 7-Zip using the following parameters: Compression parameters: Archive format: 7z Compression level: ...
19
votes
2answers
3k views

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 ...
19
votes
2answers
7k views

How big should salt be?

I will be using scrypt to store passwords in my application. As such, I'll be using SHA-256 and Salsa20 crypto primitives (with PBKDF2). Having that in mind, how big salt should I use? Should it be ...
19
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5answers
718 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 ...
18
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6answers
3k views

Why do we ask for a user's existing password when changing their password?

In a web applications context, when a user wants to change their current password, generally they would have to enter their current password first. However at this point, the user has already been ...
18
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5answers
5k views

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 ...
18
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4answers
2k views

My credit union is reducing its maximum password length to 10 characters

I just received an email from my credit union saying they are redesigning their online banking service and that I will need to change my password by October 22 to conform to the new limit of 10 ...
18
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6answers
5k views

How to avoid scripts with hardcoded password? [duplicate]

I have some scripts on Ubuntu Linux machine that logs in to a database server to run some maintenance daily. To login to the database, I need a password and right now it is hard-coded in the script. ...
18
votes
2answers
8k 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 ...
18
votes
3answers
9k views

Password in file .php

My connection.php file stores the credentials to connect to the database. <?php $objConnect = mysql_connect("localhost","username","password"); mysql_select_db("selectDB", $objConnect); ?...
18
votes
5answers
1k views

Is there any legal reason to save a cleartext password?

I called customer service of a well known company and discovered that the operator had the ability to view my website password in clear text on her screen. I asked her about this and she defended the ...
18
votes
6answers
3k 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 ...
18
votes
3answers
5k views

MySQL OLD_PASSWORD cryptanalysis?

The password hash used for MySQL passwords prior to version 4.1 (now called OLD_PASSWORD()) seems like a very simple ad-hoc hash, without salts or iteration counts. See e.g an implementation in ...
18
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1answer
1k views

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 ...
18
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6answers
6k views

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 ...
17
votes
6answers
3k views

What extra security does a 2-step website login process with a PIN provide?

I am currently working on a web application with a significant security risk attached to its function. We're using Microsoft Identity Framework to handle user logins, with the system forcing strong ...
17
votes
3answers
18k views

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 ...
17
votes
6answers
3k views

Correct terminology when describing password security to layman

I am writing a page for our website which describes the measures we take to keep our customer's information secure. On this page one section describes how we keep their passwords secure. We are ...
17
votes
7answers
2k views

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)?
17
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5answers
3k views

Is this idea for a password manager secure? If so, why doesn't anybody use it? [closed]

I've been thinking of a problem with usual password managers: although they do provide better security than manually using passwords, there's a central database that can get lost, get compromised, etc....
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
votes
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 ...
17
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3answers
12k views

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, ...
17
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5answers
3k views

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 ...
17
votes
2answers
11k views

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
598 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 ...
17
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2answers
3k views

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 ...
17
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2answers
2k views

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 ...
16
votes
6answers
5k views

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 ...
16
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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?
16
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7answers
7k views

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. ...
16
votes
3answers
799 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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5answers
5k views

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
votes
3answers
4k views

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 ...
16
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5answers
1k views

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?
16
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3answers
1k views

Does it make sense to choose a longer password than the output of a hash?

Let's take MD5 for example: It outputs a 128-bit hash. Does it make sense (in theory) to choose an input (password) which is itself longer than 128-bit? Does it increase the probability of a ...
16
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5answers
73k 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 ...
16
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11answers
6k views

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 ...
16
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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
votes
3answers
7k views

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?
16
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3answers
1k views

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 ...
16
votes
6answers
47k views

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 ...
16
votes
7answers
2k views

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 ...
16
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4answers
1k views

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 ...
16
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4answers
365 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 ...
16
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2answers
4k views

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 ...