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

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Are excessively strong password requirements counter-productive? [duplicate]

Some sites have strong requirements. E.g. Your new password must: be at least 8 characters long (longer passwords are more secure) contain at least 1 uppercase character contain at least 1 ...
2
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1answer
70 views

php's password_hash with system wide salt [duplicate]

I'm thinking about using password_hash function for generating password hashes. I have read that own salts shouldn't be generated and instead use the default one that the function generates. Own salts ...
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2answers
73 views

How can i Identify and use hash function given enough text and their hash?

So, I have this old program currently in use, as i have access to the database i have adopted all data i need except the user passwords.. Now users will provide me with the plain text password and ...
2
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2answers
99 views

When is a group password for a closed circle of users acceptable?

I am developing a tool for a company, that takes some technical data and creates PDF reports. In the tool you have several text fields, which get filled by the database. If the user wants to, he can ...
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1answer
180 views

When I register on a website, is there a way to know whether or not the site admin will be able to see my password? [duplicate]

It seems to me that whenever I register on a website, there is absolutely no guarantee that the administrator will not be able to decrypt and view my password (if they even bother encrypting my ...
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1answer
95 views

Android auto complete and passwords

I have an Android phone and when I enter a password in a password field (bank application or other), the auto complete system proposes to complete the password. I expected password not to be saved by ...
64
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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 ...
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1answer
91 views

Checking a salted hash against known password?

I've created a mysql dump of my users and passwords and awked them into a presentable form: Passwords: '...
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3answers
1k views

Client-side BCrypt, store salt and hash separately in MySQL database [duplicate]

I’m developing an Android app with a MySQL database for storing user login credentials. I’m using jBCrypt for hashing passwords before storing them in the database. On registration, the password is ...
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2answers
299 views

How to create dictionary to prevent weak passwords?

I've been tasked with adding a "dictionary check" against user's passwords to prevent weak passwords. Unfortunately, that is about as much guidance as I've been given and I need some help deciphering ...
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7answers
5k views

How to prevent username and password matches when changing a username?

Let's say that I have a system where one of the security requirements is preventing users from choosing a password that matches their username. Usernames are not case sensitive but the passwords are. ...
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1answer
105 views

Unable to completely enforce password policy

PCI DSS has a few requirements regarding the password policy (like remember last four passwords, change password every 90 days, use at least seven numeric and alphabetic characters and more). These ...
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1answer
25 views

Principal Password in Kerberos KDC database

Is there a way for me to merge a bank account number, fingerprint image and IMEI of a phone into a single entity that I could possibly use as a password in the Kerberos KDC to uniquely identity a ...
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1answer
80 views

Is there a way to securely check if a password is one of the most used ones?

So lets's say that a user wants to register to some website. For whatever reason, I want to not allow that password if it is one of the top 100 passwords used on my site (So I'm not checking against ...
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3answers
223 views

How can I prove that my software is secure for those who are interested to install it?

I've written a password locker program for Microsoft Windows that encrypts its contents to the local machine. The only way to get the data out is with the encryption key the user knows. It uses the ...
2
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2answers
68 views

Would a multilingual Diceware password be more secure than a monolingual one? [duplicate]

I've been reading up on Diceware recently, and I'm wondering if using a mix of languages would make it even more secure. On the face of it, it would force a potential attacker to consider an even ...
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2answers
112 views

Password based Asymmetric Key generation

I am looking for a password based key derivation scheme that results in an asymmetric key pair. I have worked with PBKDF and its variants but could not come up with any way of generating a key pair. I ...
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2answers
208 views

Pin delivery: SMS, mail, or pin mailer?

Imagine a scenario where a 4-digit pincode needs to be delivered securely to an end-user. Several possibilities exists: Pin mailer (this seems to be standard according to ISO 9564-1) SMS Email Email ...
2
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1answer
157 views

How might a PIN based Web authentication scheme work?

I'm interested in implementing PIN based authentication for a web application, similar to what Facebook provides in their mobile web site. Here is the user flow: User visits the site for the first ...
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0answers
36 views

What is a straightforward way to brute force CLI applications?

This is a question to maybe more CTF-experienced guys among you. I wonder how you generally brute force a simple CLI application. For example if you have an application which tells you a user's data ...
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2answers
71 views

Custom word list generation for a specific web domain

I am looking for a tool that generates a set of word lists based on the words it finds on the pages of a particular web domain. This question has an answer that generates permuted word lists starting ...
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3answers
586 views

1Password for team how secure it is?

I would like to ask you opinion about how secure is the 1Passowrd for Teams. For someone who doesn't know how 1Password - Personal use - works here a summary: You create a master password (hard to ...
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3answers
178 views

Are longer passwords safer even if the encryption/database security used is compromised?

Let me preface this that I am having a lot of trouble wording my question. Hopefully my description will help clarify. I have always wondered if long passwords actually provide you any more security ...
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1answer
173 views

Is Trillian application unsafe? (Got “Someone has your password” message from Google)

Trying to connect to GoogleTalk from the Trillian app for Android (a universal instant messenger app), I got denied even with the correct password. Then Google e-mailed me saying that my password is ...
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2answers
160 views

Password may not be similiar to last 5 passwords [duplicate]

SAP NetWeaver has a password policy to prevent your new password beeing similiar to the last 5 passwords. Are the passwords stored in plaintext to verify this? Or is something like a soundex value ...
0
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1answer
102 views

Is Entropy all that matters in a Password? [duplicate]

My question is, is it more reliable having a password that is composed by words like FootballPractice more secure than using a password that has only 2 or 3 bits less, for example FootbalPractic , my ...
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1answer
72 views

Distinct error messages for wrong email / password

I want to continue discussion started in this question "Username and/or Password Invalid" - Why do websites show this kind of message instead of informing the user which one was wrong? but ...
2
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1answer
58 views

Remembering email in login form

After logging out Google remembers recently used email addresses in the login form so the user only needs to enter the password. See accounts.google.com. How secure is it? What factors should I ...
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1answer
30 views

Creating secure random output that is repeatable across machines [duplicate]

I'm having trouble figuring out a solution to this problem. Basically what i am trying to do is create random data that can be repeated across multiple machines by a user but is also secure from ...
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6answers
278 views

How secure is this process for creating passwords?

I've been research into how to be as secure as possible when it comes to password security for online services and websites. Obviously there are some big no no's like using dictionary words, using the ...
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7answers
389 views

Strong password vs. restriction on number of attempts

To begin with, I am considering the password protection of standard internet services like Gmail or Dropbox. They often force users to choose a "strong" password, that is many characters, including ...
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2answers
72 views

Securely generate a rng seed using a small number

I'm trying to figure out a secure method to generate a rng seed to a rng using a small pin number that is 5 digits. The issue that i can see with this is an attacker could very easily just loop ...
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1answer
98 views

How much more difficult does it become to crack a password when appending a 5-digit pin?

I have a quick question regarding password cracking. Lets say you append a 5 digit pin on the end of your password. An example would be instead of a password of "password" it would be "password12345"....
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1answer
71 views

Why is the password field blanked in the registration form if the validation fail? [duplicate]

Is it really a problem if you send back the password when the validation fail on a registration form? I understand that the html that is sent back could be cached on the computer of the person ...
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3answers
2k views

Why can't the FBI copy the contents of an iPhone they are trying to crack?

Making the news rounds now is a story about the courts ordering Apple to disable the automatic deletion of data after 10 failed password guesses. What I don't understand is, why doesn't the FBI just ...
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1answer
45 views

What are the exclusions for using a very long and random password? [closed]

It is a good practise to always use long (63 character) and random passwords. Question: But what are the exclusions? Can someone mention cases? Example: when console login is needed (so not via ...
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2answers
79 views

Using emoticons in passwords

I'm coming up with a password to use for my banking website, XKCD style. Furthermore, I'm considering adding in an emoticon (say, a <3) How many bits of entropy does an emoticon add to my ...
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3answers
340 views

Why is encryption bad for passwords?

We use PGP for almost everything and it's so infeasible to bruteforce that it's considered secure. This is the guiding principle beyond CryptoLocker. But for stuff like e-mail, SSH and HTTPS, it's ...
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0answers
118 views

Can password hashing both client side and on the back end improve security if we don't necessarily trust the server? [duplicate]

I want to know if it ever makes sense to hash a password client side and rehash it again on the back end. I've not seen this done before which makes me suspicious as to whether it really does add ...
3
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5answers
352 views

How should I store a physical written copy of my password? [duplicate]

I can employ all the fancy encryption and the randomest of passwords to my hard drive, but it won't do me any good if I don't remember how to log in. It seems sensible to write down my password, then....
0
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1answer
167 views

Brute force a hard drive when most of the password is known

I need to access a hard drive that is encrypted with LUKS. The password provided is incorrect, however it is only incorrect by a character or so. The password itself is very strong and above 30 ...
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0answers
67 views

Is that a way break Linux user password by bypassing grub protected?

The best way to delve into others Linux machine is by editing the grub. Many will start by, editing the line ro quite splash as rw init=/bin/bash during the startup (usually by pressing button e on ...
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2answers
222 views

Is it a good idea to combine words from different languages to increase a password's strength? [duplicate]

I was thinking of a way to generate a password that is easy to remember, but hard to crack, like the famous "correct horse battery staple" suggested by XKCD, also discussed here, and I've realized I'...
1
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1answer
149 views

My iTunes account got hacked and someone used it to buy in-app purchase. How could that happen? [closed]

The account was hacked, I found out in my credit card statement and Apple support gave me refund which is nice. I wonder how it happened, and if there are even more serious risks that I don't know. ...
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2answers
165 views

Security concerns of running auto-login script on server-side?

I would like to fetch data from a website to do data analysis on a server. Username and password are required for login to the website. Therefore I will need to run an auto-login script on the server. ...
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2answers
225 views

How to securely transfer password from a registration page to the database [duplicate]

What steps must be followed to send password securely from the user registration page (i.e. client side) to the server over a non encrypted channel (http) when the user registers for the first time on ...
4
votes
2answers
213 views

Location of Password Hashes on a Windows Local Machine?

"Where are the two locations that user's password hashes are stored on a local windows machine?" My place of business asked me this question. I know that the SAM stores password hashes, where would ...
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0answers
33 views

Passwords vs keys in cryptography? Which is stronger and safer? [duplicate]

Maybe it isn’t correct question, but how to compare passwords and keys in cryptography? Symmetric encryption, e.g. AES, usually encrypts data with passwords, and all public-key cryptography use open ...
3
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1answer
107 views

Can I Prevent Internet Explorer from Storing Login Requests in Memory?

Using Internet Explorer 11 I have been able to login to HTTPS web applications by providing a username and password and then subsequently logout. Whilst the browser process is running I can then dump ...
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1answer
130 views

How can one securely hash passwords server side while avoiding DoS?

It is generally recommended that one use a slow hash function to hash passwords. However, does this create a DoS risk?