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

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Dealing with systems that store/send passwords in plain-text [duplicate]

Possible Duplicate: What to do about websites that store plain text passwords When using a system as it was designed to be used, and the system provides proof that it is storing and/or ...
8
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2answers
814 views

Should user be allowed to save password in browser?

The auditing company found a bug "The Auto-complete form attribute is set in password field". They suggested to disable autocomplete for this field to prevent disclosure of it "when working on shared ...
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2answers
4k views

How big should salt be?

I will be using scrypt to store passwords in my application. As such, I'll be using SHA-256 and Salsa20 crypto primitives (with PBKDF2). Having that in mind, how big salt should I use? Should it be ...
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3answers
3k views

Reverse-engineering one-time passwords for two-factor authentication systems

Given a one-time password generator that is time-based (such as Google Authenticator), how many instances of (time, PIN) pairs would one need to significantly weaken the algorithm to a point where one ...
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1answer
661 views

Token Based Authentication & Pass-the-hash Attacks

Do token-based authentication solutions (such as RSA SecurID) mitigate tools like incognito and/or pass-the-hash tools?
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4answers
546 views

What is the best way to hand out passwords to a widely spread diverse employee base?

I have a problem I need to solve - specifically, how to hand out passwords to people in a variety of locations, and with a wide variety of access. I've thought of some options, but there are ...
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3answers
1k views

Why do some websites force users to come up with difficult passwords?

I can't understand why we commonly force users to come up with difficult to remember passwords. * Your password must contain at least one number, one uppercase character, and one special ...
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1answer
226 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 ...
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4answers
2k views

Hacking computers, scifi or reality

I was watching The Girl with the Dragon Tattoo, and this female hacker was really good at hacking. My question is, how is it possible for her to crack passwords besides the brute force approach? I ...
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1answer
1k views

Bcrypt as a key derivation function?

I read a lot of entries at stack exchange about bcrypt and why it is supposed to be better than PBKDF2 in terms of password storage. I'm asking now if bcrypt is better than PBKDF2 in terms of key ...
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5answers
2k views

Is my bank storing my password in plain text? [duplicate]

My bank (and every bank I've come across) only ever asks for individual characters from my password when logging in. Is my bank storing my password in plain text?
3
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1answer
492 views

Best security algorith for storing passwords [duplicate]

Possible Duplicate: Which password hashing method should I use? I want the best cryptography algorithm for storing passwords in database, which one should I use and how can I implement ...
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2answers
2k views

openssl_digest vs hash vs hash_hmac? Difference between SALT & HMAC?

openssl_digest vs hash vs hash_hmac I want to use SHA512 for storing password. Which of the above methods are best to use? Why? What is the difference between SALT & HMAC? I just read ...
8
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1answer
447 views

Protecting emails in your database

It's common to encrypt passwords in the database, but I'm wondering what solutions are out there to protect emails in your database. Not just from hacking, but from disgruntled employees or engineers ...
8
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5answers
539 views

Utility company does not hash passwords in the database

I had to use my utility company's online account information application and forgot the password. Going through the steps of resetting the password I was emailed the password in the open. I found this ...
3
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1answer
3k views

What algorithm/encryption type does Gmail use for security?

In the wake of the recent database hacks, i.e. Sony, Gawker, etc.. where the hackers have access to the hashed usernames and passwords, i've been more keen in paying attention to the sites and ...
23
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5answers
3k views

Do spaces in a passphrase really add any more security/entropy?

I often see passphrase suggestions written as a sentence, with spaces. In that format are they more susceptible to a dictionary attack because each word is on it's own as opposed to a large unbroken ...
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4answers
8k views

Regulations that specify password length?

I have read: PCI DSS 1.2 SOX 404 AR 25-2 ISO 27001 But only PCI DSS specifies a minimum password length. Are there any other regulations that dictate password lengths for any industry? NIST ...
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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. ...
2
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2answers
152 views

How can I protect a client's mirror of the server's database?

The scenario is as follows: There are clients that users can access and work with. These clients can be online or offline. There is a central database on a server, holding all the authorization ...
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3answers
15k 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
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3answers
377 views

Is it safe or even common to cache bcrypt checks in-memory

In a web application that (as a side effect of implementing the password anti-pattern) stores passwords, one recommendation is to bcrypt to store them (or computationally expensive one-way salted ...
4
votes
1answer
395 views

Thoughts on creating unscalable conditions to brute force even small passwords?

I stumbled upon something called "scrypt" which claims to add fixed time/space complexity requirements into password-based key derivation. Quoting from their page: A simple password-based encryption ...
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6answers
8k views

Is AES encrypting a password with itself more secure than SHA1?

This isn't really a practical question, but more a question of curiosity. I heard a CS professor recommend stepping up from md5ing passwords not to SHA1, but to AES encrypting the password using ...
18
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1answer
5k views

Can a dictionary attack crack a Diceware passphrase?

Everyone knows the words used in Diceware passwords (all 6^5 = 7776 words are published) -- they're all common words. Everyone seems to know that we're not supposed to use dictionary words for ...
5
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4answers
6k views

How secure is Windows Auto-Logon?

Obviously, if auto-logon is enabled, anyone who can gain physical access to the PC can use the PC. That's not the question. The question is, when I enable auto-logon for my Windows 7 box, will there ...
4
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1answer
2k views

Rainbow tables, generation and lookup, preferably using GPU

1a) What software can I use to generate my own rainbow tables, preferably software that can utilize CUDA or ATI Stream? One of the reasons I want to make my own, is that I want to use a specific ...
3
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1answer
428 views

Non English password dictionaries

What is a good resource for wordlists used in auditing passwords in non english languages. I have extensive wordlists in English ranging to several GB's, but can't find similar resources for other ...
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6answers
1k views

Is putting every username and password for our organization in a giant Google spreadsheet a spectacularly bad idea?

Our startup has something like 100 usernames and passwords to keep track of, and we can't keep track of all of them. Would putting all of them in a Google spreadsheet shared amongst ourselves be a ...
4
votes
4answers
841 views

Store a password to avoid user interaction

I am creating a windows service that sends email to a user. It uses a Gmail account to send the email, so it needs a password to access the account. It also needs to do this automatically, without ...
9
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6answers
1k views

Cracking long Windows XP passwords

Completing an assignment for my Ethical Hacking unit at University at the moment and the first task I have is to crack some passwords. Decided to use backtrack to crack some passwords from a Windows ...
2
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4answers
625 views

passphrases - lowercase and dictionary words

Amid all the discussion about password length vs. complexity (summarized by the famous xkcd strip and the followup dicussion) I am trying to make up my mind about passphrases made up with dictionnary ...
9
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4answers
774 views

Is using a flash drive as a base for security a safe thing to do?

I'm developing some software for schools. I've found severe flaws with the current popular school LAN protection that I feel needs fixing so I plan on releasing my own software. One the those ...
6
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5answers
25k views

Modern high quality password dictionary

Has anyone come across any good password dictionary lately? Some of the lists I found dated back to 90's! Some are simply too big that I doubt their quality. There appears to be some work by someone ...
4
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1answer
983 views

Is a public known password protected Wifi more secure than one without a password?

When connecting to a public Wifi from a café for example, some don't use a password and some do. If they do use a password it is often publicly known to everybody around. Does having a password on ...
10
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2answers
6k views

Is it safe to store the password hash in a cookie and use it for “remember-me” login?

I want to store an encrypted string of the password hash in a cookie and use the hash to lookup the user and log them in (if they want to be remembered). Is this safe? The password is one-way hashed ...
5
votes
3answers
3k views

What are the odds of brute-forcing an archive with 256-bit encryption?

I have a file (a stand-alone archive). I lost the password to it, but it has been encrypted using 256-bit encryption. The password is some 20-odd characters long (including non-alphanumeric ...
3
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2answers
299 views

How does one make password easily forgettable?

Is there any phycological research that appears relevant to making passwords easily forgettable under adverse circumstances? Circumstances might include when under duress, after some duration of ...
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2answers
2k views

What algorithms are best be cracked by GPU?

What algorithms are best being attacked by a GPU powered password cracker? For example, I heard that md5crypt that is being used in unix shadow file, is not the best choice for GPU cracking because it ...
5
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6answers
869 views

What is the use of password encryption?

Why do we encrypt passwords? Is it to protect the password from eavesdropping? to protect the password after saving it in database? both? or for some other reason?
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3answers
327 views

How to test if a browser add-on is safe

I came across this plug-in that started some alarm bells ringing. The add-on would help submit a website to web directories. The first 100 submissions are free, then you need to pay $20 via pay-pal ...
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2answers
2k views

Keepass client on Android (reliable one)

I need some advice to choose a Keepass client on Android phone which can synchronize using Dropbox. As i keep all my passwords in one place, I would like to keep it safe. Is KeepassDroid client safe ...
3
votes
2answers
1k views

How is WEP/WPA2 key derived?

When I was a kid, WEP had a 40 bit key. Later, they came out with a 128-bit key. But as we all know, WEP was so badly-designed that the RC4 key length didn't really matter much. Ignoring this, my ...
2
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2answers
660 views

How to make a certificate encrypted flash drive?

I was wondering if it possible to encrypt a flash drive (or any other external medium) using certificates instead of a password. The idea is to have a number of encrypted pendrives that can be used on ...
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4answers
9k views

https security - should password be hashed server-side or client-side?

I am building a web application which requires users to login. All communication goes through https. I am using bcrypt to hash passwords. I am facing a dilemma - I used to think it is safer to make a ...
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3answers
56k views

How difficult to crack keepass master password?

How easily could someone crack my keepass .kdbx file if that person steals the file but never obtains the Master Password? Is this a serious threat, or would a brute force attack require massive ...
6
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2answers
7k views

Is it possible to speed up WPA/WPA2-PSK cracking using a rogue AP?

We know that WPA/WPA2-PSK uses a PTK (Pairwise Transient Key) for each client to encrypt the communication. This PTK is generated through the process known as 4-way handshake. As told in the related ...
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5answers
3k views

How to catch a gmail hacker/money-scammer? (in conversation with one right now!)

My friend's GMail account was recently hacked and the perpetrator sent out one of those classic "help I was mugged, I need money" style e-mails. (Edit: I know it's legit; my friend called me to tell ...
10
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3answers
315 views

Is there any conceivable reason to prevent a password change in an authentication system?

I connect to the VPN of another company with a company-specific username and password (they aren't giving everyone the same password to every company to access it or anything ridiculous like that.) ...
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4answers
1k views

Is it “standard” to SMS passwords?

When I get credentials for a new machine, my company will often send the login id in email, then SMS (or sometimes Skype msg) the password. This is obviously in order to separate the login and ...