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

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5
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1answer
521 views

What techniques do web services use to identify password theft?

I've noticed that some web services use a security scheme in which log-in attempts that have some unusual characteristics trigger extra authentication steps. For example when I try to login to my ...
0
votes
1answer
670 views

How long would it take to brute force the AES encryption?

I'm trying to write a secure code that can keep my site users passwords as safe as possible. Now I'm fairly new to encryption and would like some professional opinions and suggestions. As well as a ...
3
votes
3answers
222 views

Proper storage/use of salted passwords?

If a salt is not stored along with the hashed password in the database, is it possible that the password is salted? I ask because in a system I am working on there is only a password column, but when ...
0
votes
0answers
750 views

Why do you need to login after you change a password? [duplicate]

I can't recall a website that after resetting my password I was automatically logged in, I had to type the password again - which seems quite silly. From a security perspective, why do websites do ...
31
votes
4answers
3k views

Is it safe to show users why their password is not allowed?

/////////////////////////////// Updated Post Below //////////////////////////// This question has received a lot of hits, more than I ever thought it would have on such a basic topic. So, I ...
2
votes
3answers
327 views

Is there any reason I shouldn't use SHA1 of salt + website name + master password for my password in websites?

I considered writing a program to do the above for websites I only intend to use for short-term use.
31
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5answers
2k views

Are there any guidelines for passwords that need to be read out loud?

I recently saw the movie Olympus Has Fallen. Like in many action movies, at the end a missile is launched, and the hero (Mike Banning, played by Gerard Butler) has 60 seconds to recall the launch in ...
4
votes
2answers
196 views

Does adding a non-entropic part to a password makes it less secure?

Suppose I'm encrypting a file via AES using a password of my choice, or creating a TrueCrypt volume using a password and no keyfiles. Which of the following two passwords would be more secure: ...
2
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3answers
3k views

Microsoft password email reset link leads to different url?

...I am really annoyed and unsettled by the password reset email I just received from Microsoft. What should I think of this? My email client correctly told me that the underlying url is not the same ...
4
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5answers
237 views

Modes of Attack on Time-Bombed Password

I'm one of the co-founders of plaintextoffenders.com. We recently received a submission for which I'm not sure if there is a means of attack or not. The site in question is a hosting/VPS/etc. company. ...
0
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2answers
227 views

Using authentication only one time passwords [duplicate]

I would be interested in advice. Imagine a authentication mechanism where users are authenticated ONLY using some code (e.g., one time password) which they receive (say as SMS) on their mobile phone? ...
33
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4answers
2k views

Why did my provider reset my password after someone else attempted to gain access to my account?

Recently a provider (of SIP trunking services) I subscribe to sent me a strange email. It claimed that someone in another country attempted to reset the password to my account and was unsuccessful in ...
22
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2answers
5k views

Does bcrypt have a maximum password length?

I was messing around with bcrypt today and noticed something: hashpw('testtdsdddddddddddddddddddddddddddddddddddddddddddddddsddddddddddddddddd', salt) Output: ...
5
votes
3answers
973 views

How often should I reset my salt?

I'm thinking of implementing a salt recycling scheme on my user credentials database. The motivation behind this decision is that even if the attacker manages to get his hands on the database and has ...
1
vote
1answer
786 views

How bruteforce works code wise

I was wondering how bruteforce methods work from a code level. How does the code get access to a login page for example and insert information into the necessary fields? And is the code able to ...
3
votes
2answers
515 views

Is mt_rand() suitable for generating a salt?

Assumed I have to following code in order to generate a random blowfish salt for saving a new password: $blowfishCharacters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789./'; $salt ...
8
votes
2answers
430 views

Secure password management

I've recently begun using Keepass for my personal password management. I am setting it up to sync between my home PC, work PC and mobile device using dropbox. I'm going "all the way", and have ...
3
votes
2answers
739 views

A protocol to authenticate users without login/password

A casual message exchange on reddit yesterday got me thinking whether it might be possible to design a protocol that removes the need for users to remember a unique password for every service (s)he ...
-2
votes
1answer
720 views

What are some good user login/authentication libraries or protocols to use with Python on Google App Engine? [closed]

I've read elsewhere (http://forums.udacity.com/questions/6028436/bcrypt-not-suitable-for-pythongae) that bcrypt is not suitable for use on Google App Engine. What are some good ways to create a user ...
0
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2answers
205 views

Is my domain registrar storing my password in cleartext? [closed]

I called my domain registrar (unnamed here but not difficult to find out and a major provider) about a year ago to have them change some DNS settings. While on the phone, the customer service rep had ...
5
votes
1answer
192 views

Single point of failure: can US government requests for passwords be a vector for attack?

In recent news, CNET has reported requests for passwords, hashing and/or encryption algorithms and salts from U.S. government agencies: The U.S. government has demanded that major Internet ...
5
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2answers
1k views

What's the best way to send and receive lots of login credentials?

I'm currently a web developer for a company with lots of different remote clients. There are lots of usernames and passwords that I need to know so that I can do my job. When I first started, I was ...
5
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1answer
111 views

Is it acceptable to generate salts with a hash of the username?

Salts are supposed to be unique and randomly generated for each user when storing passwords. Is there a reason why we can't generate these salts with a cryptographic hash function using the username ...
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vote
2answers
113 views

What is more secure: single long hash, or combination of two shorter?

Fictitious scenario: User accesses a restricted data (available online) identified by random string (supported by captcha to make brute-forcing more difficult). So data is not protected by a ...
8
votes
3answers
2k views

Is this code snippet good enough for password hash and salt

After a few days reading up about salting and hashing passwords, I found an actual bit of code that tells how to do it. This is what I found: $blowfish_salt = ...
8
votes
4answers
3k views

SHA-512 unix passwords. How secure are those hashes, really?

I came across this very alarming sounding thread which indicates a GPU with about half the compute capacity of the GPU currently powering the monitor I type this on is capable of 11.5k c/s. I'm not ...
5
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5answers
942 views

Is it a good idea to use an input by the user as SALT?

I have read many Q&As here on IT Security about password hashing and salting. I am building a simple registration form for our community website which will be used by our members to create their ...
2
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2answers
189 views

Eye-Tracking, Public Access Points and Password Protection [closed]

Could entering sensitive keyboard input in public places with camera systems equipped with a robust AI possibly leak keystrokes via eye-tracking technology -- assuming the typist is using the ...
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votes
1answer
172 views

Can Cain&Able Crack SSL? [closed]

I have been messing around with Cain and Able and used APR on another computer (also mine) to get a hashed version of my username and password for my yahoo e-mail account, but I seem to be lost as to ...
10
votes
1answer
311 views

Is this cross-site password model secure?

I'm looking for a way of securely having passwords for different pages. Say I generate this password: ild23rfsfdfg%*#fArg34t34657%537@asd7oak2094^*q2k2k@Kk3j4tn453Q5# Then, for each site, I change ...
1
vote
2answers
659 views

Why is unshadowing needed?

john /etc/shadow look like working, because john will use many-many CPU for it. But why is unshadowing needed? Why isn't it enough to use "john /etc/shadow"? Because of the salting? Can someone ...
4
votes
2answers
780 views

Would a massive blacklist of guessable passwords be useful? [duplicate]

Suggestions to make a good password all focus on creating a string that a computer (or more likely, a network of computers with multiple GPUs) can not guess. Putting a password meter for when users ...
4
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3answers
1k views

How can salted, hashed password storage be combined with a plaintext, nonce and hash based authentication?

My understanding is as follows: To securely store a password (e.g. in a database), you use a hashing algorithm designed for this purpose (designed to be slow, e.g. bcrypt), and you use a unique salt ...
2
votes
1answer
978 views

How do I generate a blowfish password hash in Ubuntu?

What's the command line to generate a blowfish password hash? I can't seem to figure this out at all. Apache's htpasswd only supports bcrypt, and openssl passwd doesn't even do blowfish hahes (but it ...
6
votes
3answers
414 views

Should password be cleared after unsuccessful logon attempt?

Lets assume following workflows a) On a device with keyboard: I type my username and password Press enter [realization] I made a typo Password field is cleared: not a big deal, I can type ...
16
votes
7answers
1k views

Taking password letters not whole one, is this secure? [duplicate]

I found a site which is taking password letters from their users not the whole password. Is this secure? Or do they have saved password as salted hash (MD5)?
4
votes
3answers
469 views

Encrypted files storage. How to simplify the password management scheme?

It's probably dublicate but I can't figure out the correct keywords for search. You can help by just telling me those words, I'm rather good with Google :) I want to develop somewhat like file ...
30
votes
3answers
2k views

Is there a security reason for a site to limit the number of times a user can change their password?

Is there a security reason to disallow a user to change their password as frequently as they want? I have found this security policy in a site and I am not sure why it is enforcing it. One reason I ...
4
votes
4answers
435 views

Is a short sudo password ok?

On a server I control, I have disabled password logins (public key only), but still need to enter my password to access sudo. This is becoming cumbersome, as I use a long, automatically generated ...
2
votes
3answers
739 views

Should I take care when entering incorrect passwords in untrustworthy websites?

I have the problem that I usually use 4 passwords that I use quite often. I use the first two strong passwords for very important services (e.g. Email, PayPal,..), and the other two not so strong for ...
9
votes
4answers
1k views

How dangerous is it to store password in plain text on sites like GitHub?

I have a few private repositories set up on GitHub for some of the projects I am working on for my company. These applications connect to databases and I have database authentication credentials ...
6
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2answers
646 views

Detecting Pass-the-Hash

I was wondering what you guys are doing to detect attacks like Pass-The-Hash within your network. I've read about Breachbox ...
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1answer
1k views

Retrieve Admin Password from router [closed]

There is a way to retrieve a router admin password without hard reset? I'm loggen on LAN and know username and local ip address... TKS
3
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3answers
260 views

Are there implementations of password hashing algorithms for major frameworks that utilizes specialized hardware like GPUs/FPGAs?

It is common knowledge that password cracking attempts can greatly benefit from specialized hardware such as large clusters of GPUs or FPGAs. Are there any implementations of the commonly recommended ...
2
votes
1answer
1k views

What are realistic rates for brute force hashing?

I'm trying to gauge password strength assuming that the attacker has a hash of my password. Can anyone cite some realistic contemporary rates at which someone could perform various hashes? I know most ...
0
votes
1answer
414 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 ...
2
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5answers
314 views

Is accepting old passwords a bad policy?

This question is inspired by an experience I had today with online banking, as follows. One year ago I opened an online deposit account. (Without naming the bank, I will say the company is currently a ...
8
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3answers
388 views

Does setting a user password on Windows XP help protect against remote exploits compared to no password?

In a typical home user situation with a PC connected to the internet via a router, suppose we are not concerned with protecting the machine from people with physical access. Does setting a password on ...
4
votes
2answers
557 views

Is there a risk in sending the username in a password reset email?

We're using a CMS that has a password reset function that works according to best practices out of the box. Passwords are stored as salted hashes Forgot Password works like this: User enters ...
4
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2answers
310 views

How can I create a secure password?

I know the standard tricks, create a long password, numbers, symbols, capital letters, etc. My questions is how do I judge password security. I heard different tricks to make secure passwords. For ...