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

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1answer
70 views

Password sent over TLS: threats other than TLS compromise?

One of my findings during a security audit was a password, sent as is over the network. As bad as it sounds, this happens only over HTTPS connection. Some authors suggested here that additional ...
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3answers
98 views

Why shouldn't I use an old password? [duplicate]

Some services like Google or Facebook forbid me to use a password that has already been use for the same account in the past. My question is, if this old password was never compromised (i.e it was ...
-1
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0answers
89 views

Enter the 1st 3rd and 12th character of your password [duplicate]

Some businesses such as banks and insurance companies ask for specific letters of your password. For example a bank asks for the 1st, third, and 12th character of your password. Would this be less ...
7
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1answer
87 views

What's the most secure way to circumvent encryption to enable password recovery?

I have a web app (which I've talked about here before). Users can use it to save people's contact details. These contact details are encrypted to ensure that they are difficult to get at if they're ...
6
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3answers
188 views

Authenticating a user via SMS

I'm involved in a project that's building a chat-bot that users can communicate with via SMS from their mobile phones. We'd like the users to be able to use the bot to do some basic account-management ...
3
votes
1answer
73 views

Creating accounts on sites with no security?

I'm sort of confused about security on some sites. Here on stackexchange.com, for example, seem to have no security normaly, but as you log in or create an account, it uses keyexchange and an ...
9
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1answer
130 views

Handling “forgot password” functionality with encrypted data without security questions

As a sort of follow-up to this question on handling password-reset functionality when dealing with encrypted user data, is there any good method for resetting a user's password in an encrypted web ...
24
votes
5answers
990 views

Would turning a Diceware phrase into a sentence decrease its security?

Diceware passphrase lengths are on the rise - up to six or seven words now. The old adage that passphrases are easier to remember may be true for shorter phrases, but six truly random words can be ...
6
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2answers
93 views

Is it good to store passwords in a separate table/database and manage them in a separate process?

I'm quite a newbie at systems architecture and security so I just want to check that this plan makes sense. I'm building a web app and I need to store a password for each user. I've already read ...
20
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4answers
1k views

When encrypting cloud-stored data, is it acceptable to use the user's account password?

I'm developing a web service that stores sensitive personal information (such as telephone numbers, addresses, full names, and email addresses) in a database, such that it can be accessed from ...
0
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1answer
155 views

How long will it take to break a salted password?

Let's say that I have a system where all passwords must be 8 characters long and each character can be any 32 different values. All my passwords are hashed with a salt. I can test 64 passwords per ...
2
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2answers
107 views

Where to store a pepper?

Assuming you're using a pepper in your password hashing, where should it be stored? I know you shouldn't store it in the database since it can easily be found there during a dump and the idea is to ...
0
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1answer
58 views

How to conceal a computer in operation with a separate logon password?

Goal: Disallow physical people near the computer to see its operations. No password to start the computer. But, I'd like to conceal the screen after startup and all programs loaded. Because of the ...
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votes
2answers
75 views

Creating secure passwords [duplicate]

I have been tasked with writing a random password generator to be used on a series of throw away accounts. In this scenario, the accounts need to be very secure and will be deleted after a single day ...
80
votes
10answers
9k views

Is there a threshold for a password so long it doesn't get any more secure or even becomes insecure?

I always hear "A long password is good, a longer password is better". But is there such a thing as a "Password is so long it is becoming unsafe" or "Password is long enough, making it longer won't ...
3
votes
0answers
57 views

Is it possible to use parallelism when computing a key derivation function for a single password/key?

Suppose I have an AES-256 encrypted file, and I want to derive the key using PBKDF2 and a given salt with a large number of rounds (say 1 million), but I'm limited by user tolerance for UI lag when ...
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6answers
152 views

Is the password FFFFFggggg&&&&&22222 safe from being guessed? [closed]

It is 20 characters long, mixes alphanumeric and special symbols. It is one among ** 20.
7
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2answers
1k views

philosophical: restricting the password space increases security

This is more of a philosophical question. Suppose that you are trying to choose a good password for a particular online service, say your bank's e-banking service. Now the bank has some restrictions ...
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 ...
4
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3answers
115 views

Is emailing a password recovery code as bad as emailing a password in plain text? [duplicate]

I am creating a mobile app where my password recovery feature involves sending a password recovery code (randomly generated string) to the user's email address. They get the code, then enters it ...
8
votes
2answers
105 views

How can I enforce strong password policy with non-technical user base?

I've been using zxcvbn to enforce strong passwords for a service where break-ins would cause considerable problems. However, the service is only viable if many users sign up. We've found that users ...
3
votes
3answers
107 views

Is it insecure to reveal if a password is being used for another account after a set period of time?

Password reuse can be considered a pandemic of security. The obvious way to fix this is to encourage people to use password managers, but (comparatively) few people actually do. My idea is to have ...
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votes
1answer
66 views

Do you consider PWGen safe to use?

Do you consider PWGen safe enough to use? What do you use to make truly random password. PWGen should be using "movement of your mouse" to make it really random, right?
139
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5answers
10k views

What to do if stuck with website that has poor security?

I have a student loan account with a company, not the biggest company but big enough to where they should have their act together. Today I couldn't remember my password to log into my account ...
3
votes
5answers
241 views

Recommended level of password complexity for Keepass

I want to start using a Keepass master password that I can easily remember. Let's take this sentence: I really hate blue mountains, and let's make it one password: ireallyhatebluemountains. Is this ...
3
votes
1answer
48 views

Membership.GeneratePassword

I am looking for a method to generate a onetime password for provisioning purposes in ASP.NET-MVC. I came across the Membership.GeneratePassword which is in the System.Web.Security namespace. Is this ...
4
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1answer
68 views

Is limiting/cutting password-length without notice insecure?

I have encountered that our linux system cuts the length of every password to a certain length, after that length every additional character seems to be ignored. Does this make our linux system more ...
3
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3answers
144 views

Prevent password reusing across different sites

I'm generally against too strict or complex rules to accept passwords (rules like "It must contain at least one upper-case character, one number and one symbol" and things like that, see also XKCD ...
4
votes
1answer
97 views

Is using OAuth for login less or more secure than maintaining your own passwords?

Pros: The complexity in managing passwords is maintained by a company with stronger security policy. Let's assume they secure passwords properly. The user doesn't have to maintain yet another ...
3
votes
1answer
43 views

Single randomly generated passphrase for both identity and authentication

There are questions about using a password only to identify and authenticate a user, rather than an email address or username plus password: Why do we authenticate by prompting a user to enter both ...
1
vote
1answer
47 views

What are the advantages of a ZKP authentication system?

So, I read somewhere that Zero Knowledge Proof based authentication is good because it makes sure that the server does not store your password and neither is your password being transmitted over the ...
2
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4answers
214 views

Are limited length passwords a security risk? [duplicate]

I found a webpage where users can be registered. However, it seems that the length of the password must be between 6 to 12 characters. Is that a security risk?
0
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0answers
15 views

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
57 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
63 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
votes
2answers
84 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 ...
6
votes
1answer
177 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 ...
4
votes
1answer
73 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
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 ...
0
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1answer
69 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: ...
9
votes
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 ...
9
votes
2answers
218 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 ...
32
votes
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. ...
3
votes
1answer
87 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 ...
0
votes
1answer
23 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 ...
0
votes
1answer
73 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 ...
5
votes
3answers
218 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
votes
2answers
49 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 ...
0
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2answers
96 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 ...
1
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2answers
113 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 ...