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

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2
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1answer
144 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]----+ | ...
1
vote
1answer
134 views

How to suspend a silent oberserver from Facebook account?

A friend of mine told me about the following problem: She used to login on Facebook on a computer of her boyfriend. After they broke up she recognized that he was able to login to her account from his ...
1
vote
0answers
105 views

Password automatically typed into user box on facebook [closed]

Just want to ask some questions regarding on this strange experience while logging on my account on Facebook There are cases that I'm accidentally typing my password into the username box of the ...
0
votes
1answer
116 views

How many passwords should I have? [closed]

So I am upgrading my personal security. Most passwords that I use are generated by and stored in a password manager. There are a few places where I cannot use a password manager -- here, I plan to ...
131
votes
8answers
15k views

Why are salted hashes more secure?

I know there are many discussions on salted hashes, and I understand that the purpose is to make it impossible to build a rainbow table of all possible hashes (generally up to 7 characters). My ...
1
vote
1answer
127 views

Finding Plaintext Password Repositories [closed]

I came across a file, that was used by our tech support, to store all generic usernames and passwords in them for use with new systems. (Our company has been trained on the use of other Password ...
11
votes
3answers
13k views

Is a password protected PDF file safe for bank statement attachments?

My bank emails my monthly statement to me in a password protected PDF attachment. Is this a secure method of transmitting something as sensitive as bank statement?
3
votes
1answer
800 views

Are passwords stored in the cookie? encrypted?

Whenever I connect to security.stack.exchange, I am automatically logged in. I haven't allowed the browser to store my password. When I delete all cookies stored by the security.stack.exchange, I have ...
9
votes
3answers
369 views

Security of pronounceable passwords

Some random password generators support the generation of pronounceable words of any given length n. Assuming that words are derived using 26 lowercase letters, the number of possible words of length ...
5
votes
2answers
518 views

SSH key auth, but still need password for sudo?

SSH with public-private key authentication comes enabled by default with most Linux distributions. This is great because when I create accounts for remote users I don't have to email them sensitive ...
2
votes
1answer
225 views

How Windows Server 2008 Stores Local Users Passwords?

It is not clear to me how Windows Srver 2008 R8 stores local account passwords. Is there any salt added or just NT hash is computed and stored. The following article describes all the methods used by ...
1
vote
1answer
188 views

How to safely use a Key Derivation Function to secure private data - need guidance

I have some secure data created in my client app which I wish to store on the server as backup for the user. The user already has a password to authenticate with the server. The password is never ...
20
votes
10answers
4k views

Password Management within an Organisation

Within an organisation there are many passwords such as those for root accounts on servers, hosting accounts, router logins and other such things, that need to be kept track of. I know in some ...
3
votes
1answer
182 views

Regarding Windows password and Chromes Remember password Feature

Google Chrome browser helps in password management by prompting users to remember their passwords for the websites. These saved passwords can be accessed from the browsers "settings" menu, and to do ...
9
votes
2answers
2k views

How does Google not care about “spaces” in Application-specific passwords?

I have recently setup "2-step verification" for my Google account. One of the features is the ability to create "Application-specific passwords " for devices that do not support the 2 step process. ...
55
votes
13answers
8k views

Do we really need a long and complicated password for websites?

Most of websites that handle important information (Gmail, for instance) have some kind of brute force protection. Sometimes if you try more than X times it will lock the account or at least give you ...
5
votes
2answers
1k views

Does the Kerberos KDC know the users' plaintext passwords?

In http://www.freebsd.org/doc/handbook/kerberos5.html section 15.7.8.3 “The KDC is a Single Point of Failure” you can read: By design, the KDC must be as secure as the master password database is ...
13
votes
5answers
2k views

Why should I have secure passwords for sites that I pay bills on?

What's the worst that can happen, the hackers will pay my bills for me? Assume that this isn't a malicious hacker out to disconnect my electricity. What kind of concerns are there for my finances, ...
57
votes
12answers
10k views

How reliable is a password strength checker?

I've tested the tool from Microsoft available here which tests password strength and rates them. For a password such as "i am going to have lunch tonight", the tool rates it's strength as "BEST" and ...
17
votes
7answers
1k views

How different should my passwords be? [duplicate]

Suppose I use remember one long high entropy master password, and use variations of it for each of my passwords. Eg if I remember tSaF4nWeACVkUU4 as a master password and use tSaF4nWeACVkUU4t (with a ...
1
vote
3answers
125 views

Site allows both Partial and Complete password authentication; do they have my password in plain text? [duplicate]

My bank provides online banking facility like most of the banks these days. On the web they have Partial Password Authentication. Although I don't really believe in PPA providing extra security but ...
44
votes
8answers
6k views

Do bad passwords produce bad salted hashes?

When you have a password stored in a database that has been strongly hashed and salted does it really matter if the underlying user password is weak? If you setup features like limiting login ...
0
votes
1answer
148 views

John the Ripper password cracker is viable?

Is this still viable? I remember using this when it just worked in shells. http://www.openwall.com/john/
3
votes
2answers
126 views

Similarity comparisons with hashed passwords possible?

At a company I worked at, I had to change my password every 90 days and I could only reuse a password after 8 iterations. This no-reusal included passwords being too similar to the old one, e.g. when ...
8
votes
6answers
978 views

Is it useful to protect hashed password with encryption?

Imagine that I am hashing the users' passwords with a random, long enough, salt, using key stretching, and a secure hash. Would it be more secure to finally encrypt the hash with a symmetric key?
4
votes
3answers
741 views

Question about a simple strong password management system

I am designing a system which requires access control via a strong password and for that purpose will use a password generation algorithm A that produces a strong password of length L >= 32. The ...
3
votes
1answer
334 views

Perfectly Robust Hashing Scheme, or Completely Over-Engineered?

This is going to get long, so prepare. Basis of the question is, Do all these steps improve security, or am I completely overthinking the problem? Are my assumptions/thought process valid? We all ...
2
votes
5answers
898 views

Looking for password manager in company [duplicate]

I was looking for solution everywhere, but maybe because lack of specialized words I can't find it. I've got a problem in finding a program, but I don't know how to describe it in one word so I'll ...
-1
votes
1answer
46 views

ICloud and Quality Password [duplicate]

How many 'random' characters should my iCloud password be if it were going up against the BEST hackers and the best hacking software?
-2
votes
1answer
51 views

Is digested password safer than salted password?

which scheme is the better one in your opinion? I know that both are secure but which is better one? I know that digested passwords are very difficult or even impossible to decrypt. Thanks for your ...
1
vote
1answer
61 views

Multi hash security [duplicate]

Is md5(sha1(pass)) more secure than md5(pass)? For example in case of sqli when attacker cant get our hashing schema, brute force or dictionary attack would be much less efficient. Am i right or is it ...
3
votes
5answers
339 views

How to deal with password schemes that can produce weak passwords?

Introduction Since the xkcd note on password strength, there has been a lot of attention for password entropy. However, this raised the question: what if you used a strong scheme, but happened to ...
20
votes
9answers
1k views

Is a simple, but very long password a good password?

Is a password like wwwwwwwwwwwwwwwwwwwwwwwww9 (25x 'w' and a number) secure? It would be easy to remember.
9
votes
8answers
1k views

Sequential password updates

Let's say I have a reasonable KDF, and that I make users change their passwords periodically and keep some old password hashes to prevent password reuse. What's to stop the user from changing the ...
0
votes
2answers
62 views

What is the solution for handling exceptions in password hashing schemes?

There is a technique called password hashing that describes creating unique passwords based on a unique master key and a static and arbitrary hash value. Using this technique, the user only has to ...
2
votes
2answers
196 views

Should email verification be followed by password-based login? Why?

[This is a duplicate, considered off-topic at http://stackoverflow.com/questions/26564992/should-email-verification-be-followed-by-password-based-login-why] A typical account creation process seems ...
0
votes
0answers
210 views

Is the password “Z” more secure than the password “a”? [duplicate]

Okay, I guess it's not possible to call one-letter-passwords "secure" - so let's compare ZZZZZZZZZZ with aaaaaaaaaa. Both are using the same character pool [A-z], so the number of combinations for a ...
1
vote
0answers
174 views

How does an attacker authenticate to a service using just the hash of the user (after performing a pth attack)

Let's say the attacker got the username and the password's hash. How can he use it when authenticating to some service in its domain with NTLM , for example? How can he send the request as the ...
0
votes
0answers
230 views

oclHashcat error messag in Kali Linux

I am in the process of learning oclHashcat syntax. Currently, I am working on breaking a file of md5crypt strings with a dictionary file. The dictionary I am using is rockyou.txt from an installation ...
3
votes
3answers
184 views

Why require new users to change password?

I have noticed that it is common practice when setting up a user account (Windows users accounts and Google Apps user accounts in my case) to require new users to create their own password immediately ...
23
votes
11answers
4k views

One liner to create passwords in linux?

How do you create a readable password using bash with one line? What if i'm looking for 128 bits of entropy? EDIT By readable I mean the 94 printable ascii characters (without space). It can use ...
0
votes
2answers
135 views

Passwords: Symbols and length > 20 disallowed [duplicate]

I'm going through a bunch of accounts at the moment changing my passwords, some of them are looking a little weak and i've reused them, but i keep coming across websites that don't allow you to use ...
1
vote
2answers
93 views

Facebook security

I check my security settings (from my Facebook acc.) from time to time, and sometimes I see there are IP addresses which logged into my account but don't belong to me. When I look in the web who is ...
3
votes
6answers
11k views

Hardware USB Key to Reset Any Windows Password

This tool requires physical access of course, and there are many things you can do once you have physical access, but this peaked my curiosity. The tool in question: ...
5
votes
3answers
240 views

When form submission fails, password field gets blanked, why is that the case?

I've recently asked a question about blanking the password fields in UX for usability purposes, but It seems all the sites use this approach for security reasons. Why is it insecure to post back the ...
43
votes
6answers
3k views

Is the option to jump to blanks in password fields a security risk?

Using Ctrl + ← / →, it's a common behavior across different operating systems to jump from word to word (or from blank to blank) in text input fields. Now I've discovered that this also applies on ...
-1
votes
3answers
568 views

Gmail, Yahoo, Hotmail , and so on; How do they check the content of an attached password-protected archived file like Winrar?

How is it possible that mailing systems like Gmail, Yahoo, and Hotmail are able to check the content of an attached password-protected archived file like WINRAR, if the password cannot be guessed, ...
-1
votes
2answers
11k views

Recover Windows Server 2003 admin password through restricted user

OK, so here goes after a lot of trial and error: background: My client recently took over another firm. However, apparently the administrator passwords to the server (along with some other non-IT ...
12
votes
6answers
2k views

What is the simplest safe way to convey a password to another person? [duplicate]

What is the easiest way for two people – neither of whom are computer specialists and cannot meet in person – to send a password for an encrypted file that is attached to an email? The two simplest ...
1
vote
4answers
160 views

Password recovery flow - Send Password recovery to any email?

I am building a new MVC app. Considering this "forgot password" flow: 1)You enter an email. 2)You press "send recovery password". 3)An email awaits in the inbox, pressing the link in it brings you to ...