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

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3answers
98 views

Sensitive issue regarding windows 8 password [closed]

Although I know this sort of request probably isn't exactly what stackoverflow is for, I am desperately seeking help. One of my best friends recently passed away and his parents asked me if I knew a ...
2
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3answers
113 views

Use the same password on different (very secure) sites?

I understand that one should not use the same password everywhere, as stated here for instance. Using the same password on several non-valuable sites may be considered acceptable: we simply do not ...
5
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5answers
2k views

Salted password + hash - is it really useful? [duplicate]

I am new to the topic and wanted to know the concept of having salted hashes before going down to the technical details. From what I have understand password - plaintext hash password - plaintext ...
7
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8answers
647 views

Password reset with lost email functionality

I have searched and viewed most of the other questions and answers about implementing forgot password functionality on a website. However, we have a unique situation. When a user registers an account ...
4
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2answers
237 views

Does adding a non-entropic part to a password makes it less secure?

Suppose I'm encrypting a file via AES using a password of my choice, or creating a TrueCrypt volume using a password and no keyfiles. Which of the following two passwords would be more secure: ...
1
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1answer
66 views

Prevent brute force attacks on web publishing logins

Presumably, if someone tries to brute force into your website's control panel at your web host's site - they will be throttled/locked-out etc. But what about the web publishing logins (Web-Deploy, ...
4
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2answers
469 views

Passwordless login over email - security considerations

I'm proposing the use of a login system that sends a one-time login token (with high entropy) via email to the user. After using the token, the user receives another token via email and the previous ...
2
votes
1answer
100 views

Is it secure to set default value for password field?

I'm looking at an application where admins can "invite" users by email and invited users. Invited users then are sent a unique URL and are inserted into a MySQL database with status pending and an ...
0
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5answers
951 views

Why do we use passwords on sites? [duplicate]

I don't have passwords for my personal sites. To sign up a user pick their username and enter their email. There is a logout button if the user wishes to log out. To log in you enter your email and ...
4
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2answers
3k views

File security when encrypting files directly with the openssl command / and what about SHA1 hashing password first?

I've been using this command to encrypt files for a while now: openssl aes-256-cbc -a -salt -in secrets.txt -out secrets.txt.enc Then I type in a password. Can someone tell me, roughly speaking, ...
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4answers
4k views

What should be used as a salt?

I always hear that it is best to use salts on top of stored passwords, which then somehow gets concatenated and hashed afterwards. But I don't know what to use as a the salt. What would be a good ...
0
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2answers
117 views

Saving passwords in database

I have recently been studying a lot on writing secure code and choosing secure methods for saving passwords to a database. I'm wondering if it's secure to use ready made libraries or APIs to do this ...
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3answers
20k views

Windows 7 Password Hash Security

I recently came across a number of sources that suggest that cracking Windows user account passwords is easy by examining their password hashes. I understand that these hashes are stored in the SAM ...
81
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9answers
145k views

Where can I find good dictionaries for dictionary attacks?

I’m wondering where I can find good collections of dictionaries which can be used for dictionary attacks? I've found some through Google, but I’m interested in hearing about where you get your ...
3
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2answers
121 views

Is there any history of a major attack using password reuse? [closed]

While everyone and their favorite webcomic seems to agree that password reuse is a major problem, some quick googling cannot seem to find any cases where it has been used on a large scale in an ...
3
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2answers
390 views

Is this password generator safe?

128-bit entropy is required http://nxtra.org/nxt-client/js/passphrasegenerator.js With all new browsers (Chrome, Firefox, IE 11) it uses crypto.getRandomValues which should be safe, but with IE 10 ...
6
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3answers
402 views

Am I in this particular case allowed, to store password in java program?

I have a Java-Server program running on Ubuntu-Server which gets every 5 minutes current location data of my android-smartphone (which I carry with me). My architecture is the following: My smartphone ...
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1answer
113 views

What type of hash is this MD4(MD4(($pass)).(strtolower($username))) [closed]

Can I decrypt this hash? Domain Cached Credentials: MD4(MD4(($pass)).(strtolower($username)))
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2answers
401 views

*NIX shadow file password format

I'm trying to get shell access to a router and have managed to retrieve its /etc/shadow file: root:$1$$N76hdwGfg11g0KdKbtyh21:0:0:root:/root:/bin/bash I've tried to use john to crack it but ...
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2answers
66 views

How does the password become 30,000 times stronger?

This google support page says: For example, an eight-character password with numbers, symbols and mixed-case letters is harder to guess because it has 30,000 times as many possible combinations ...
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3answers
10k views

Can password-protected zip files be broken without brute force?

You have a zip file that you created with 7z to password-protect it with AES 128. Can a smart adversary extract the data only through brute force, or is the file vulnerable to other attacks - such as, ...
9
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1answer
97 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 ...
0
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0answers
89 views

Windows Credentials - read password

What is the cipher used by windows Credential Manager to generate credentials backup files (*.crd)? With a backup file from Credential Manager and the password used to created that backup file is it ...
3
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1answer
94 views

Can OpenVPN monitor my passwords in my browser?

I want to know if I run OpenVPN when I want to log in to websites (like Gmail etc.....) is my username/password in danger? Can they monitor saved passwords in my browser or anything else? I'm new to ...
5
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3answers
198 views

Should I set a password for 'root'@'localhost' in MySQL?

The 'root'@'localhost' MySQL account can only be accessed by someone currently on the server hosting the MySQL server. Assuming that only the person or persons who are in charge of the MySQL server ...
0
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1answer
159 views

Lock Windows to a specific app

Is it possible, using some program or application, to lock Windows 7 so only a specific app can be used, for example Word, until a password is entered? Thanks!
0
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1answer
789 views

How does a password authentication over a TCP protocol actually work?

When coming up with a password based login protocol, many solutions come in mind: User sends password in plain text. Compute hash on Server, compare to hash in database. - Bad because attacker can ...
2
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1answer
119 views

How much does knowing the zxcvbn password strength help an attacker?

On an answer to the question How critical is it to keep your password length secret?, Mike Ounsworth commented that by storing the zxcvbn-calculated entropy of a password you make it easier for an ...
2
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1answer
128 views

Where to store hashes, salts, keys in Desktop Applications

I am trying to figure out where or how i should store application secrets and keys inside a desktop application. For example a facebook app key or dropbox key and secret. So I've read that i should ...
2
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1answer
101 views

Is it insecure to provide a hash of an AES password?

I have made some software that encrypts and decrypts files using AES. I was wondering if it is safe to write a hash of the password to the file so that the program can check if a password is correct. ...
24
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1answer
2k views

Facebook password lowercase and uppercase

Recently I logged into my Facebook account and then noticed that my caps lock was on. So I tried to log in again with and without capslock on. I got in both times. Then I tried to log in with the ...
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1answer
88 views

Is a ZIP file password easy to break? [duplicate]

I thought that ZIP file passwords were a fairly decent protection. I came across this video, that seems to indicate otherwise. https://www.youtube.com/watch?v=SqRSNuJSm4o [12 minutes view time] ...
4
votes
2answers
114 views

Reset links in password expiration emails

Our organization is rolling out yearly password expiration to our 40,000+ users this fall and we have been socializing this change for some time now. However being such a large organization, our users ...
5
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4answers
456 views

Bad password policy at my bank

I logged in to my bank tonight and was prompted that all customers were being forced to change their passwords for "security reasons". The policy for new passwords is: 6 to 10 characters, no special ...
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1answer
74 views

Why should I include a client_id in an OAUTHv2 password grant request?

Like little red riding hood, you don't know who is knocking on the door... Why even bother accepting a client_id in case of a API <-> Javascript-website or API <-> Android App password grant ...
20
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4answers
3k views

How secure is Snowden's MargaretThatcheris110%SEXY password?

In an extra from Edward Snowden's interview with John Oliver, Snowdon advises that a good password to use is one such as MargaretThatcheris110%SEXY.. Also, on the Errata Security blog, Robert Graham ...
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1answer
81 views

Make really personalised wordlist file

i want to make a really customised wordfile with: 4 letters first + 2 numbers example: divo11 or yeve11 And not like this: p0oiw1 or u4hf3e This wordfile is really important. How can I do it?
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5answers
604 views

How much is the entropy of a randomly generated password reduced if I regenerate until I get a password I like? [duplicate]

In many of the answers and comments on the well-known XKCD #936: Short complex password, or long dictionary passphrase? question, the importance was stressed of generating the password randomly, and ...
15
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2answers
1k 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 ...
29
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7answers
4k views

Do non-keyboard characters make my password less susceptible to brute forcing?

I can put characters in my password for which there are no keys on a keyboard. On Windows, Alt+#### (with the numpad) inserts the character for whatever code you type in. When I put this in a ...
9
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4answers
7k 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 ...
87
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11answers
12k views

How critical is it to keep your password length secret?

Is keeping your password length secret critical to security? Does someone knowing that you have a password length of say 17 make the password drastically easier to brute force?
5
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1answer
202 views

Is Django's approach to password reset tokens secure?

I am implementing a password reset feature for a web application and am contemplating adopting an implementation similar to Django. In a nutshell, Django creates a token who is comprised of a ...
1
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0answers
126 views

WifiPhisher not creating a fake access point

I recently came to know about WifiPhisher. To test it, I set up an access point using my Windows laptop and tried to obtain its password using this tool in my Ubuntu machine. So, when I run the ...
4
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3answers
531 views

Encrypted files storage. How to simplify the password management scheme?

It's probably dublicate but I can't figure out the correct keywords for search. You can help by just telling me those words, I'm rather good with Google :) I want to develop somewhat like file ...
4
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1answer
113 views

How to detect a database leak

Website keep getting hacked every day and every now and then we hear website owners react and tell "affected users that their password might had been compromised". Most sites that disclose such leaks ...
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3answers
2k views

How are leaked government credentials possible and what's the point?

In the wake of all these leaked/stolen/hacked government login/passwords being stolen it got me thinking. How is the leaking of these passwords even possible? Or are they of any real use? Aren't all ...
2
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1answer
75 views

Save Password length after hash to minimize calculation

Reading this topic How critical is it to keep your password length secret? following scenario comes to my mind: Assume I've a web application (PHP written using password_hash()) using salted password ...
4
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1answer
114 views

Bash scripting and password input

I am writing a bash script and prompt the user for his password. This password is supplied for either a local or domain account to query a MS SQL Server (using sqsh and freetds). How secure is the ...
2
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1answer
155 views

Dump linux password in clear text

Is it possible to dump a Linux password in clear text format? In Windows it is possible to do so using "Windows Credential Editor".