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

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3
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3answers
294 views

When changing a password, does it have to be completely different?

When changing a password how important is it to have a significantly different one? For example is it bad to reverse the sequencing of the old password to make a new one or change a few numbers?
3
votes
5answers
176 views

Are there any academic articles on how people handle their passwords?

Are there any academic articles on how people handle their passwords - how many they use in total, how often they change it, whether they commonly store it somewhere or just remember them and so ...
3
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1answer
3k views

Are Windows password hashes salted with the user name?

I'll readily admit I'm pretty clueless when it comes to cryptography, so there may already be some false assumptions in the question title itself :-) Still, I "heard" that it is more secure to store ...
3
votes
2answers
613 views

What is considered a reasonably high iteration count?

I copy-pasted a function that implements the PBKDF2 hashing algorithm in PHP. The function asks for the amount of time that I would want it to loop in order to produce a hash. Now, I'm wondering, ...
2
votes
4answers
132 views

Is it a good idea to to use secure_hashing_function(mypassword.url) as my password? [duplicate]

Like many users it's very difficult for me to use a different password for every website I have an account with. It does not matter how complex my password is if ONE naive website stored it in clear ...
2
votes
1answer
824 views

Password-less authentication in web apps - How safe it is?

I read a long time ago this article about how could work a Password-less Authentication System, which sounded to me like a great idea. I even built it in a small fun little application for fun. To ...
2
votes
0answers
54 views

Disallowing Similar Passwords [duplicate]

Upfront, I want to clarify that I am not a professional cryptographer, I am more curious about playing with the math and science behind it, and also want to improve my habits with my own personal and ...
2
votes
1answer
651 views

Key's random art image is mostly black

I have generated an SSH key on Ubuntu 10.04 with ssh-keygen -t rsa -C "example@example.com" and the key's random art image comes out mostly empty (modified slightly): +--[ RSA 2048]----+ | ...
2
votes
2answers
418 views

Temporarily save failed logins password hashes for using against brute force attack

My question is about online brute force attacks, that try to authenticate in the website. 1) For the first case if the requests are coming from the same ip, I think this are relatively easy as after ...
2
votes
1answer
420 views

Is there more risk in changing administrator password locally vs from a centralized location?

I'm working on a mechanism to better handle group policy passwords in response to MS14-025. We formerly used this mechanism for setting the local admin account passwords on our workstations (primarily ...
2
votes
1answer
2k views

Brute-Force GPU Password Crackers

Brute-force password cracker programs which claim GPU support include John the Ripper, ighashgpu, oclHashcat, and others. oclHashcat appears one of the more popular, but I am not sure which AMD/ATI ...
2
votes
1answer
2k views

Using John the Ripper to crack SHA hash w/ partial knowledge

Group, I have a SHA1 hash that I would like to brute-force. I have knowledge of several characters before and after the password (ie, if the hash is derived from "xxxpasswordyyy", I know both xxx and ...
2
votes
1answer
284 views

Password checking in the context of symmetric encryption

It is my understanding that block ciphers like AES don't have any built-in mechanisms to verify data integrity upon decryption, although some modes of operation might provide that. I played around ...
2
votes
0answers
97 views

How can a service shorten a password if it is not stored in plaintext? [duplicate]

Possible Duplicate: How can Microsoft validate a shorter password on Microsoft accounts (MSDN)? My Microsoft password was 18 characters long and when I updated to Outlook.com it started to ...
2
votes
2answers
729 views

Using a tabula recta to store passwords

Reading an answer to another question ("Is there a method of generating site-specific passwords which can be executed in my own head?") I came across this link, describing a way to use a physical ...
1
vote
3answers
172 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 ...
1
vote
4answers
255 views

Complex password rules - is there any sense?

Let us assume that our system is well designed and it limits the amount of login errors so that brute force attach on the user interface is not possible. Say after 5 failed logins for an account the ...
1
vote
4answers
234 views

How to store passphrase in this situation?

How to store a passphrase with a Java application that periodically needs access to its plaintext form? It is a strange situation, but I am wedged in it. If providing a decent security mechanism is ...
1
vote
1answer
257 views

Can accounts still be logged onto if Password Caching is not enabled?

This is kind of an extension of my other question.. If you were not storing any of the passwords locally (caching disabled), would a user some how still be able to circumvent around this security ...
0
votes
1answer
121 views

Starting a new job after working at home for years. How to best protect data, secrets, and privacy in the workplace?

I have just started interviewing for new computer job after years of working from home. At home I feel very secure with how I protect myself from data loss and keeping my secrets secure. I backup ...
0
votes
5answers
1k views

What if I develop my own hash algorithm to create strong passwords from easy ones?

I came up with this idea but I cant figure out if it's good or bad, maybe you can help. My goal is: I want to create extremely strong passwords for my main accounts (gmail, skype and so on). I want to ...
0
votes
2answers
119 views

How do you overcome the problem of the salt being public and known by the attacker? [duplicate]

I believe that when adding a salt to the password you need to store the values so you can compute the hash again. But, what does happen if the attacker get the salt? How is it possible to add value ...
0
votes
1answer
458 views

How to encrypt files without giving the user access? [duplicate]

I don't know if I should ask this question on security.SE or stackoverflow, so please move my post if necessary. I want to store my (C#) application data in a way that the user cannot read or modify ...
0
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2answers
2k views

Long Passwords: How are they more secure? [duplicate]

Possible Duplicate: XKCD #936: Short complex password, or long dictionary passphrase? How are long passwords more secure? The only situation in which I can accept long passwords are more ...
-1
votes
2answers
128 views

Using a password hash…as the password? [duplicate]

Ok, this is probably a really stupid idea, but I can't really see why it would be a bad idea. Maybe someone can enlighten me. Why couldn't you enter a password good hashing algorithm like bcrypt, ...
-1
votes
1answer
6k views

Hydra bruteforce is giving wrong passwords. Can't seem to work any help? [closed]

Ok so what im actually trying to do is to bruteforce my own account on some website just to check myself . This is NOT for illegal steps or use , im trying to crack my OWN password , and im trying to ...
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votes
3answers
699 views

find password and iv of an encoded string knowing the decoded string

If I would know the clear and encoded versions of a string could I somehow find the password and.or iv that wore used to encode it? Encoding done with open_ssl aes-128-cbc.