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

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2
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4answers
3k views

LDAP vs MySQL for Usernames and Passwords

I understand the LDAP databases are more secure, but is it always necessary to use LDAP instead of MySQL for usernames and passwords?
21
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12answers
3k views

Why do we even use passwords / passphrases next to biometrics?

In the last couple of days there were a lot of talking about passwords and passphrases, not only here, but on several blogs and forums I follow (especially after XKCD #936 saw the light of this ...
5
votes
4answers
230 views

Should we be checking password restraints on log in forms?

We have many restraints we put on users when they set up their password. These restraints include password length, characters they can or cannot use, the use of numbers and letters, capitalization ...
7
votes
3answers
1k views

What are the security implications of using TOTP for single factor authentication?

(Note: I am not actually planning to do this. This question is strictly theoretical.) TOTP is commonly used as the second factor in Two Factor Authentication. It is an open standard with available ...
2
votes
1answer
61 views

HMACs that have the same key and message

im using HMACSHA256 to generate the hash of password and store it. the objective here is to just authenticate users, i.e - save their hashed passwords, and validate users whenever needed using the ...
1
vote
0answers
97 views

How secure is a password app that stores both the password and two factor secret in one place?

Take for example 1Password, that now can store your password and one time password secret in a single place (your 1Password vault). I know it isn't truly two-factor anymore, but how much better is it ...
2
votes
2answers
181 views

Combining SCRYPT + a short crc

I'm considering using SCRYPT for password storage. (I'm open to PBKDF2 as well, or bcrypt by itself). The issue is that I don't want this to become a potential point for a DDOS attack, given the ...
6
votes
5answers
37k views

How to generete dictionary for brute force attack?

I need to crack my own password. Advantage is that I know possible characters and maximum length. What I need is to create dictionary for brute force attack. Dictionary should contain all the combos ...
0
votes
2answers
296 views

Hashing request - What type of hash this?

I have a text which is hashed using several layers of hashing. The final hash looks like 2E55A1DD65AB839E62362DEF86D329D7. What type of hashing can it be? How can I find out what kind of hash sum I do ...
1
vote
3answers
82 views

How to compare passwords with duplicate password

On Steam, the gaming client, I have this habit of creating multiple "smurf" accounts. I have a randomly-generated, unique password, and I decided to use the same password for all of my multiple ...
0
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0answers
20 views

Chrome/Youtube says incorrect certificate for host? [duplicate]

Why my Youtube always ask me: Incorrect certificate for host. The server presented a certificate that doesn't match built-in expectations. These expectations are included for certain, high-security ...
15
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3answers
3k 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 ...
50
votes
8answers
4k views

Is it OK to tell your password to your company's sysadmin?

I'm working in a small company (20 employees) as a senior software engineer. After having problems with my email, our newly employed IT administrator asked me to write my user password to someone in ...
7
votes
6answers
25k 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 ...
0
votes
2answers
56 views

How does RealVNC Enterprise Know My System Credential?

After the installation of RealVNC on a Windows computer, the default login username and password via VNC is the same as the system username and password. Can anyone tell me how RealVNC can access such ...
0
votes
3answers
86 views

When to set security questions for a web application?

For enhanced security, we can use security questions and use them as a means for users to reset forgotten passwords or as an additional means for authenticating. When would we be the right time to ...
2
votes
3answers
158 views

is it feasible to improve the entropy of XKCD #936 by using a larger dictionary?

XKCD #936 uses a limited subset of the English language, only 2000 words. I just looked it up, and the English language has over a million words, a sizeable subset of those having special characters, ...
1
vote
1answer
968 views

John the Ripper - Calculating brute force time to crack password

I'm using incremental mode (brute force) mode in John the Ripper to crack Linux MD5 passwords. I'm trying to calculate the time it will take to run through all combinations of 12 passwords (with 12 ...
12
votes
5answers
2k views

What is the best way to transmit password hash over unreliable TLS?

I have TLS connection between my server and client. I have no certificate, so the connection is susceptible to the Man-in-the-middle attack. I fear that attacker could intercept the password hash ...
333
votes
21answers
60k 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 ...
2
votes
1answer
119 views

Crackstation “Secure Salted Password” Java example - is it really secure?

I'm making an auth service so I've been looking for some good Java/Groovy implementations of password + salt hashing. I've found this article on crackstation along with a code example and decided to ...
28
votes
5answers
3k views

Are passwords comprised of key sequences on a keyboard any less secure than the same characters but jumbled up?

Here are two passwords: 5678%^&*tyuiTYUI and 8^tyU75%*IuY6T&i Both have the same number of characters and in each the characters are identical, the only difference is that the first ...
1
vote
1answer
29 views

Can a PKCS12 file be distributed over insecure channel?

Is the PKCS12 only as secure as the password protecting private keys ? Can I distribute the p12 file over an insecure channel ?
1
vote
2answers
108 views

Will hashing passwords in my use case improve security and why?

I am developing an application the architecture of which is arranged as follows: Session host <---> Central relay server <---> Session client All communication between the initiating ...
2
votes
1answer
113 views

Is it a good idea to expire passwords after a time relative to their security?

If a user has to change their password ever so often, is it a good thing to check it against zxcvbn or similar library and assign a expiration date relative to the risk of the hash being cracked?
25
votes
6answers
6k views

Are passwords that are manually typed in really unrecoverable from memory or disk?

As part of an increase in the security measures for our company, we're moving to making sure all password logins (databases, servers, etc), are done through a password prompt and never using stored ...
340
votes
12answers
56k views

What technical reasons are there to have low maximum password lengths?

I have always wondered why so many websites have very firm restrictions on password length (exactly 8 characters, up to 8 characters, etc). These tend to be banks or other sites where I actually care ...
0
votes
1answer
87 views

Can I get rid of storing user secrets by using OpenID, and what do I need to store?

What information do you have to keep about a user to be an OpenID consumer? I want to use OpenID to let users register and authenticate on my system. So while I'm at it I want to not duplicate ...
2
votes
3answers
1k views

Store password locally. Where? How to pass it securely?

I'm developing an application. The user must enter his credentials which will be sent to the server. If the user opens the application a second time he shouldn't need to enter them again - credentials ...
0
votes
2answers
53 views

Is authenticating via the database secure

Sorry for this probably noobish question. So far, I've read password comparison/verification is implicitly understood to be made on the application layer and not in the database. For example in PHP, ...
0
votes
0answers
34 views

I forgot my ZIP file password. How do I bypass the encryption? Which software would work? [duplicate]

Should I use brute-force attacks? Do they even work? What options do I have? I only remember short fragments of the password and it's definitely more than 7 characters long.
8
votes
4answers
4k views

HMACSHA512 versus Rfc2898DeriveBytes for password hash

We are currently using HMACSHA512 in .net, with a 128Char (64byte) validation key The salt is 64 char randomly generated string. We allocated 2048 length on the database for the hashed base64 string ...
0
votes
1answer
279 views

Good password hashing algorithm compatible with PHP and Linux apps

I'm looking for a password hash method for a new server system. The hashes must be generated from PHP code and verified from PHP as well as by a number of applications on a Linux system. I know that ...
623
votes
21answers
126k 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 ...
1
vote
1answer
27 views

How can I defend against Heroku (or any PAAS) ID theft?

How can I defend against Heroku (or any PAAS) ID theft? Is it correct to assume that if someone obtained my Heroku credentials that they would have access to any data in my app, regardless of any ...
0
votes
2answers
65 views

What is the severity if someone read the ConnectionStrings_Prod.config?

I was doing an pen test in a website and the programmer did a big mistake and I was able to read any file. So I read the web.config and see the password for database was in ...
9
votes
5answers
3k views

Using Google Search results to determine password strength

Google is a repository of Internet data, as it indexes tremendous amount of data. It uses a prediction service to determine the rest of the search query. With such a huge repository in place, can we ...
2
votes
1answer
54 views

Is it sensible to use application password bypassing two factor authentication? [duplicate]

I discovered that some applications (like Sylpheed) seems unable to support two factor authentication. Google has a feature called application passwords - a separate password that "grants complete ...
7
votes
2answers
221 views

Does password-hashing “busy-work” need to be cryptographically secure

All modern password hashing schemes are deliberately designed to include a huge amount of "busy-work", to limit the speed with which an attacker would be able to conduct password hashing attempts. ...
6
votes
3answers
801 views

How to encrypt all existing customer passwords [closed]

I work for an online shop and since I worked here we have stored customer passwords in plaintext. I joined the company as a data inputter and when I discovered that we did this I flagged it up with ...
4
votes
2answers
101 views

Should password recommendations be different for devices, networks, and internet?

I started using a password manager last year and updated nearly all of my internet accounts to super-strong, unique passwords, and that isn't a problem, cause I only access them from web browsers or ...
4
votes
0answers
165 views

Any problems with scrypt yet?

In the question Do any security experts recommend bcrypt for password storage? Thomas Pornin recommends the hashing function scrypt but saying it is "too new to be recommended on a general basis". ...
4
votes
4answers
215 views

how to check for duplicate passwords

Is it possible to check if like 100 people are using the same pasword? without risking anyones password getting out? I heard google does this, not allowing the user to set a password 1000 people are ...
0
votes
1answer
139 views

When bruteforcing a WiFi network password, Can that admin see it?

When bruteforcing a captured packet containing the encrypted password, can the owner/admin of the router see each auth attempt? I'm assuming you just encrypt each passphrase in the dictionary file and ...
3
votes
3answers
496 views

Rainbow Tables: What is the Reduction Used for?

This is a follow up from this answer. The answer is very good, and it put me to thinking and doing some research. I have found another good explanation on this site. At some point, the author says: ...
3
votes
5answers
271 views

Are all unsalted password hashes inherently insecure?

Maybe I'm missing something obvious... Are all passwords stored in common, unsalted hash algorithms able to be attacked via rainbow tables?
0
votes
1answer
100 views

Brute force attacks detection risks

I would like to ask if using brute force attacks on some websites or online services can be risky in any way for the hacker? Let's say that someone is using medusa tool to crack password on his ...
-1
votes
1answer
8k views

How to get a Network's WIFI Password through CMD? [closed]

I found that Wifi's Password can be retrived using the network and sharing wizard in Windows, And Technicaly theres no way to store Passwords/collection of bytes in the memory after switching/shutting ...
10
votes
3answers
843 views

Should an admin user be able to edit passwords?

For your typical web app, should an admin superuser have the right to edit a user's password, or should only that user have the right? (Even with edit ability, the admin would never see the current ...
0
votes
0answers
24 views

How rainbow table works? [duplicate]

I have roughly understand how a rainbow table works from http://en.wikipedia.org/wiki/Rainbow_table, but I am quite curious why there is a need of different reduction functions for each column for ...