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

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7
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4answers
1k views

Password hashes should run md5 thousands of time: really?

I skimmed through How Companies Can Beef Up Password Security and I thought that several assertions were completely wrong, in particular: Cryptographic hash (like md5) with salt are bad. It isn't ...
1
vote
3answers
5k views

Storing passwords online using Gmail documents

Following this discussion about "Online Passwords Managers" I wonder whether it is a good idea to store the passwords using a spreadsheet inside Gmail documents? I mean, it seems to me that these ...
0
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1answer
940 views

What's the idea behind requiring users to change password periodically? [duplicate]

Possible Duplicate: How does changing your password every 90 days increase security? Some sites require users to change their password every x days. For example, at least 3 online banking ...
4
votes
5answers
403 views

Tool to grab sensitive information from command lines [closed]

Of the information entered on the command line (command name and arguments) have to be considered public (everyone can access it using commands like ps). Is there a known tool to automate this kind ...
4
votes
1answer
803 views

Reasonable (BruteForce) Attempts/Second Estimate?

I've read various articles on password strength and passwords vs pass phrases (including the one from XKCD and its thread here), but most of those articles seem to be focused on online passwords, and ...
5
votes
4answers
2k views

Is encrypting a salt value with a password/plaintext a viable alternative to straight up hashing?

The basic problem, as far as I can tell, is that hashing's flaw is that the password is in the hash. Asymmetric encryption's flaw is that the password is encrypted and can be reversed. The posts ...
9
votes
4answers
7k views

How do online accounts get hacked?

How does your typical users run-of-the-mill Facebook/twitter/gmail/AIM/etc account get hacked? Is it simply a matter of a weak password? Are they typically the victim of phishing or other social ...
29
votes
8answers
5k views

Why would salt not have prevented LinkedIn passwords from getting cracked?

In this interview posted on Krebs on Security, this question was asked and answered: BK: I’ve heard people say, you know this probably would not have happened if LinkedIn and others had salted ...
4
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1answer
2k views

Which cross-platform password managers support encryption using a hardware token?

I am looking for a really secure password manager and I really like the fact that Password Safe supports encryption/decryption using a Yubikey programmed in challenge-response mode. Read more here: ...
10
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3answers
5k views

Is LastPass' locally stored One-Time-Password recovery a security problem?

If you forget your LastPass master password then LastPass provides the possibility to recover access to your vault using a One-Time-Password (OTP) which is stored locally but is initially disabled. ...
6
votes
3answers
640 views

An alternative to traditional passwords: is there some merit to this idea?

If you've got a website aimed at people that are not neccessarily technically proficient, letting new users choose their own password isn't very secure because of the simple fact that a lot of people ...
5
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2answers
2k 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 ...
22
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5answers
2k views

Is it possible to increase the cost of BCrypt or PBKDF2 when its already calculated and without the original password?

I just wanted to know if you can increase the cost (iterations) of those two algorithms off-line. I want to increase the cost every year of my users passwords. One solution is to recalculate them ...
1
vote
3answers
559 views

Linux mcrypt security

I just installed 'mcrypt'. When I try to encrypt some file with DES using the command 'mcrypt -a des myfile', I am prompted for a passphrase with a maximum character count of 512. > mcrypt -a des ...
20
votes
8answers
18k views

Why do people still use/recommend MD5 if it is cracked since 1996?

It's still commonly recommended way of hashing passwords, even if it's insecurity had been proven in 1996 Therefore we suggest that in the future MD5 should no longer be implemented in ...
31
votes
8answers
5k views

Is it safe to use leakedin.org?

leakedin.org claims to offer a service checking if your LinkedIn password has been stolen and whether it has been cracked. The website claims that it's pure Javascript, that is your password won't ...
2
votes
3answers
10k views

Database field type for password storage?

In the past I used varchar(255) for storing hashed passwords (no salt). Is this still enough? Or are longer fields required?
16
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5answers
4k views

What is a good practical (and sane) way to manage all your passwords for online sites?

I am just a mere mortal that wants to have a somewhat secure way of managing all my passwords. This is something that I have been putting off, but since LinkedIn decided to give away one of my ...
1
vote
4answers
66 views

When (if ever) should web app force numerical, generated (hence hard to remember) logins?

Some bank sites force me to use system generated numerical login (ie. 8 digit number). Apart from singnificantly decreasing usability and giving impression of security (to some), does it serve any ...
10
votes
7answers
31k 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 ...
5
votes
2answers
1k views

Do OpenPGP/GnuPG apply slow hash to password when encrypting/decrypting key?

Password space is quiet small. Therefore slow hash should be applied to password before using it for encryption. Should slow hash function (like bcrypt) be applied to password before using it with ...
2
votes
4answers
2k views

Using only password to authenticate user (no “username” field)

I am creating a client access system, to allow manage invoices, make payments, access information about their products and information/functionality alike. Supposedly there are less than 1000 ...
23
votes
5answers
2k views

Should passwords be revealed in error message?

I am having pet-peeve with PHP's PDO class. As you can see on the Warning note: it reveals database password by default if an exception was not caught (when display errors is on which is a probable ...
5
votes
3answers
399 views

Is my sons' school portal in violation of any Password/UserID rules?

My sons' school sends both ID and PW for a portal through USPS at various times during the year, (e.g. class registration) whether I need it or not. If I change the password, it sends a confirmation ...
2
votes
3answers
377 views

How should one manage authentication on custom line of business software

I am writing line of business software for a company, and we want to authenticate users, so we can manage workflow and do some auditing. Basically my employers don't want me to piggyback off of ...
3
votes
5answers
169 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 ...
18
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7answers
896 views

Are common passwords at particular risk?

The question Should we disallow common passwords like “password” and “12345”? on User Experience immediately made me think that these common passwords were extremely dangerous not because they are ...
4
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3answers
199 views

Is using encryption the only viable option to thwart password sniffing?

I'm using HTTPS Everywhere on my browser to chose SSL versions of websites when available, but many sites don't offer a secure version. Is SSL the only viable option to thwart password/clear text ...
3
votes
1answer
391 views

For what malicious activity can one use a computer with a high-end GPU?

I'm currently researching what malicious activities can one do with a computer containing a high-end GPU. So far the only uses I found were Bitcoin mining and password cracking. Are there any other ...
10
votes
3answers
1k views

HMAC Based Request Signing - Storing the Salt

I'm working on a (non high security) project that currently isn't live but might go live at some point. We have a REST API (implemented using Restlet and Neo4j) running on a server and an Android ...
8
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0answers
79 views

What do studies show are best practices for password expiration policies? [duplicate]

Possible Duplicate: How does changing your password every 90 days increase security? What are best practices for password expiration policies? There are some questions that already address ...
7
votes
1answer
4k views

Does NIST really recommend PBKDF2 for password hashing?

We hesitated between BCrypt and PBKDF2 for password hashing. In many forums and blogs people say something like "In their Special Publication SP 800-132 NIST basically recommends using PBKDF2 for ...
31
votes
4answers
17k views

Standards for encrypting passwords in configuration files?

My workplace has a standard that plaintext passwords are not allowed in application configuration files. This makes enough sense on its face, in case someone gets access to the config files they ...
4
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3answers
2k views

Can the salt for PBKDF2 be a hash of the user-entered password?

I want to derive a key from a password in a client application that will be used as a master key that decrypts a data key. As far as I understand the salt should be private knowledge. Would it be ...
1
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0answers
143 views

Recover Word file password [closed]

I have a Word (.doc) file that I created a long time ago I believe in a Windows XP. The problem is I don't remember the password anymore and need to access the file. What would you recommend I do? I ...
44
votes
1answer
3k views

What's the risk if I accidently type my password into a username field (Windows logon)?

I'm used to logging into my personal Mac which is a password-only field (like waking from sleep mode). Sometimes I have to use a Windows network on which I have an account, but of course I have to ...
3
votes
1answer
517 views

Academic papers on GPU password cracking?

Are there any scientific papers or publications on GPU password cracking?
14
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6answers
864 views

Is there any security risk in storing hashed variations of passwords?

For example, if hypothetically an application requirement was to tell users when their password might have failed because caps-lock was turned on, and hypothetically there was no way for the ...
2
votes
1answer
672 views

How to download PHI PDF from a secure website to a secure, encrypted folder on Windows 7?

Objective: HIPAA compliance. Here is the process: Receive PDF File through secure website Open the PDF (Which involves downloading to some folder) No longer need PDF The Question: Is there any ...
5
votes
1answer
4k views

Is BCrypt enough when saving a password into a database?

In order to allow users to connect to my website, I encrypt their password using BCrypt since it is one of the slowest algorithms to decrypt (making a compromised database longer to be decrypted). ...
2
votes
1answer
4k views

How can I decrypt traffic on a WEP encrypted network?

Let's say that I am connected to a WEP Access Point and I want to sniff all wireless traffic inside that network. How can I decrypt the traffic even though I don't have the cryptographic key? I found ...
1
vote
1answer
196 views

Stripping / appending characters from user password before hashing to conceal it forever?

I had this idea to permanently conceal user password by requiring minimum length then stripping certain characters. For example if the user password is secret123, the system will strip it down to ...
3
votes
2answers
741 views

Can key files be brute-forced like passwords?

Let's say you use a program like Truecrypt or Keepass which allows you to have a password + key file. I understand that passwords can be brute-forced/dictionary-attacked but is the same true for key ...
5
votes
2answers
319 views

Are more passwords breached via dictionary/bf attacks or via packet-sniffers/key-loggers?

This question has always intrigued me whenever the subject of passwords is brought up. Does anyone have direct experience or a reputable source to answer what percentage of password breaches are ...
6
votes
4answers
1k views

Do password complexity requirements reduce security by limiting search space?

I've read that password complexity requirements make passwords easier to guess via brute force attack. The reason for this is that the complexity requirement actually reduce the search space for brute ...
-1
votes
1answer
427 views

What time do dictionary attack take on salted passwords?

I was reading that the designers of UNIX password algorithm used a 12 bit salt to modify the E-table of the unix hashing function (the DES). Supposing i have a system with 2^(24) users? Is that ever ...
5
votes
3answers
252 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 ...
2
votes
0answers
173 views

Lastpass - Can I just keep the previous autofills? [closed]

I just installed the Lastpass Firefox plugin, and it seems like a useful tool thus far. The only thing that drives me crazy is that I am used to the Firefox saved passwords where it will show the last ...
25
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4answers
4k views

Why is using salt more secure?

Storing the hash of users' passwords, e.g. in a database, is insecure since human passwords are vulnerable to dictionary attacks. Everyone suggests that this is mitigated via the use of salts, but the ...
-1
votes
4answers
168 views

pesudo random password

I post a question before about one password repeating to make it longer, now its a new way want to ask about, if take the word 'secure' and instead of repeating it put somenumbers between it, exp: ...