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

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2
votes
1answer
151 views

Recover password from .pfx file

I have an old Windows SmartClient application that is published with a signed certificate (a .pfx file). We want to extend the expiration date to more than one year. I've used a program called ...
10
votes
5answers
12k views

Regulations that specify password length?

I have read: PCI DSS 1.2 SOX 404 AR 25-2 ISO 27001 But only PCI DSS specifies a minimum password length. Are there any other regulations that dictate password lengths for any industry? NIST ...
1
vote
1answer
71 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 ...
1
vote
3answers
104 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 ...
56
votes
11answers
44k views

Are password-protected ZIP files secure?

Following my answer. If I can list contents of a password-protected ZIP file, check the file types of each stored file and even replace it with another one, without actually knowing the password, then ...
7
votes
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
votes
3answers
195 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 ...
9
votes
1answer
137 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
1k 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 ...
81
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 ...
827
votes
23answers
164k views

XKCD #936: Short complex password, or long dictionary passphrase?

How accurate is this XKCD comic from August 10, 2011? I've always been an advocate of long rather than complex passwords, but most security people (at least the ones that I've talked to) are ...
20
votes
4answers
2k 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 ...
3
votes
5answers
259 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 ...
7
votes
2answers
246 views

Is it easier to crack a ZIP file than a 7z archived file given they have the same password?

I am interested in knowing if either of them is easier to crack than the other because of inherent flaws.
6
votes
2answers
109 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 ...
2
votes
2answers
109 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 ...
-1
votes
2answers
76 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 ...
3
votes
4answers
380 views

Help generating wordlist using crunch

I need to configure crunch so that it produces a wordlist with the following set of rules: Exactly 10 characters long Contains exactly 4 letters, which have to be a-f (all lowercase) Contains ...
0
votes
3answers
186 views

How secure would this method be considered for password storage

Ok I am currently storing the passwords in most secure way I could think of. With use of Encryption and Hash. The passwords are first generated by user as plain-text with minimum length of 6 ...
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 ...
-10
votes
6answers
163 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.
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 ...
1
vote
2answers
278 views

Do WiFi passwords remain accessible significantly after logging in?

"... they'll go to the taskbar and look at the properties of the WiFi router to get the password." is a quote from another question on this site, and is in the context of WiFi passwords. The ...
139
votes
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 ...
8
votes
2answers
121 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
2answers
482 views

Storing a user's password in a retrievable manner

I currently store my users passwords as PBKDF2 hashes, for the authentication part of my web application. Each user also has their own private key and public key (also stored in their user profile in ...
7
votes
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 ...
9
votes
2answers
243 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 ...
8
votes
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 ...
4
votes
3answers
120 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 ...
-1
votes
1answer
79 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?
3
votes
3answers
108 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 ...
16
votes
3answers
17k 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 ...
1
vote
2answers
128 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 ...
3
votes
1answer
54 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
votes
1answer
77 views

Wordpress.org pages refresh when logging out of Gmail

I've noticed that when I change my Gmail account by logging out of one account and then logging into another, all open Wordpress.org pages refresh. Additionally, when I recently changed a password on ...
3
votes
3answers
162 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
78 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
votes
1answer
46 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 ...
3
votes
4answers
217 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?
1
vote
1answer
48 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 ...
18
votes
7answers
2k views

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 ...
6
votes
4answers
395 views

How will security need to be changed if we can crack password hashes in quasi-polynomial time?

If we suppose that we have access to some form of generalized password hacking/cracking that can somehow find an n-bit password in time O(n^(log n)), is there need for alarm? This question arises ...
0
votes
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 ...
0
votes
1answer
24 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 ...
1
vote
2answers
69 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
1answer
62 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 ...
422
votes
22answers
89k views

How does changing your password every 90 days increase security?

Where I work I'm forced to change my password every 90 days. This security measure has been in place in many organizations for as long as I can remember. Is there a specific security vulnerability ...
15
votes
3answers
11k 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, ...
2
votes
2answers
87 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 ...