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

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How much added security do I really get with a longer key size?

Imagine I have a cipher which supports keys of 128, 192 or 256 bits. Suppose that there are no vulnerabilities in the cipher regardless of key length. I'm going to use it to encrypt something, and ...
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5answers
480 views

Creating multiple secure and easy to remember passwords

I have recently developed a new web application which our clients log into using a username and password. As we're just rolling out this system, we'll be setting the usernames and passwords ourselves, ...
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3answers
310 views

How can Microsoft validate a shorter password on Microsoft accounts (MSDN)?

I recently ran across this when logging into MSDN. (I saw this screen after typing my initial credentials.) I have a 20+ digit password, however there's apparently a new requirement for Microsoft ...
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2answers
2k views

Dictionary Attack on Wifi

I know a few people with pretty weak passwords. What kind of systems exist to prevent dictionary attacks? Would it make sense to restrict the number of connection attempts in a certain timeframe? ...
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5answers
4k views

How can I avoid putting the database password in a perl script?

I have a cronned perl script that connects to our database and does various kinds of lookups and integrity checks. The original script was written by someone long ago. My job is to make some changes ...
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3answers
314 views

Increase the security of an already stored password hash

Right now we're using 1024 byte PBKDF2 with 256 byte user-specific salt and variable iterations. However, I would much prefer to be able to, perhaps once every year or two, to be able to flat out ...
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2answers
649 views

Is it better to hash n*x times in sha1 or n times in sha512 on the client side?

I already know I"m going to hash the user's password n times in either sha512 or n*x in sha1 before it is sent to the server. Once at the server, I'm going to use bcrypt set to use ~1/100th of a ...
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3answers
2k views

I don't see how “-salt” in the openssl command line tool enhances security at all

I do this to encrypt a single file: openssl aes-256-cbc -a -salt -in file.txt -out file.enc and then type in some regular plaintext password. I do not understand how -salt enhances the security of ...
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3answers
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Is a HMAC-ed password is more secure than a bcrypt-ed or scrypt-ed password?

Given an option , which one should I choose , a HMAC for storing a password securely or a bcrypt or scrypt library?
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3answers
1k views

Can ssh keyfile security be broken in a few hours if the file is exposed?

At this link there is a claim that if an RSA key has a strong passphrase security might be broken in a few hours if an attacker has the private key. Is there something weak about the security of RSA ...
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3answers
240 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 ...
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5answers
464 views

Is including a secret GUID in an URL Security Through Obscurity?

I know that this question is a little bit on the side of Opinion/Discussion, but I think there's a provable answer to it. I think the common view of "Security Through Obscurity" is that the security ...
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3answers
246 views

What is the value in asking for a second password for sensitive operations?

When a user has logged in to a system using their primary password, is there any value in asking for a distinct second password when performing sensitive functions? Does it provide any benefit over ...
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2answers
372 views

Security risks of typing wrong password

I accidentally typed my root account password on my google account login, I know google keeps their website quite safe but this question came in mind: Is there a risk if you accidentally type in ...
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3answers
672 views

Can I spoof IP addresses when attempting to brute force a login?

I am testing my website with hydra brute-force software. But accessing my apache conf remote server file, it seems that an attacker can't log-in more a limited number of times per seconds. Does hydra ...
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5answers
852 views

Storing password hashes without a correlation to the user account

I read an interesting article about an alternative way to store password hashes ans was rather intrigued. A better way to store password hashes? The primary concept is having a large table full of ...
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3answers
360 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 ...
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3answers
771 views

Attack vectors for brute-forcing website passwords

When talking about password security, a lot of discussion centers on the risk of a password being guessed in a brute-force attack. For websites where a user has registered an account, what are the ...
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2answers
203 views

Password hint storage, analysis

What are the security implications of asking users to provide password hints? What are best practices for storing user hints? What research has been done on using user-supplied password hints to ...
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2answers
321 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 ...
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4answers
2k views

Is it okay for API secret to be stored in plain text or decrypt-able?

Aren't API keys considered usernames and API secrets considered passwords? Why is it that API servers like Amazon Web Services allow you to view your API secret in plain text? It makes me think they ...
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3answers
274 views

Are there password/passphrase guessers/crackers which can utilize facts supplied about the target?

I was just reading a discussion about cracking passwords that said the person running the tool might know things about the target like the birthday of his first girlfriend's dog but the tool won't. ...
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3answers
870 views

Using Secure Remote Password without sending the username in the clear

To initiate a key exchange using the SRP protocol the client sends the username so the server can look up the salt and password verifier. Is there a simple way to change this so that an evesdropper ...
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2answers
382 views

Stolen Laptop - Next steps

My laptop (modded 2007 Macbook Pro) was stolen 2 days ago when I didn't pay attention to my backpack in a tourist spot in Europe and while I'm quite certain they won't have much use for it (the apple ...
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3answers
6k views

How to crack password hashed using SSHA?

Is it possible to crack a password hashed using SSHA if I know the salt? How can I do it?
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3answers
501 views

Security of the KWallet password encrypting application?

According to http://gaganpreet.in/blog/2013/07/24/kwallet-security-analysis/ , the KWallet password management system is quite weak, it uses key splitting, Blowfish 56, and no salt. The key ...
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3answers
440 views

Is it proper to be prompted that I entered an old password

I changed my Facebook password a few days ago. Today, I entered the old password chronically, and saw the prompt: Sorry! You Entered An Old Password And even shows the date&time when I ...
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2answers
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Considering that SRP is better than SSH and Basic Auth, how can it be implemented in a website?

SRP is short for Secure Remote Password protocol, and provides a better way for passwords to be sent over the internet. I've read the information at it's Stanford University home page, the Wiki ...
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2answers
5k 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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2answers
497 views

Implementing Secure Remote Password: Constructing the verifier

The SRP protocol as described in RFC 2945 generates the password verifier: x = SHA(<salt> | SHA(<username> | ":" | <raw password>))` v = g^x % N I have three questions: why use ...
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1answer
518 views

Reversible password storage obfuscation method for third-party login credentials

I have an internal business application, that as part of its functionality connects to a third-party app using login credentials specific to the user of my own app. These passwords are stored in a ...
6
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3answers
129 views

What standards are there for mangaging high value passwords?

I am leading a small team at a start-up and I am facing a dilemma with high value passwords. I am the only one on the team who knows all the key passwords for production servers, databases ... etc. ...
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3answers
5k views

Why is Chrome asking for the application-specific password and my account's password every time?

I enabled Google's two-factor authentication and found it ironic that Google Chrome Sync requires #1 You account password, and #2 an application-specific password. First of all, don't applications ...
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1answer
2k 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 ...
6
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1answer
530 views

When taking ownership of a TPM in Windows 7, how is the SRK derived from the password?

When you take ownership of a TPM in Windows 7 you encounter a screen like this: Based on this document, it is my understanding that completing this dialog box somehow results in the generation of ...
6
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3answers
406 views

Is it OK to use the same password for a Linux login and the SSH private key?

I want to remotely log in to my Linux server with SSH. Public/private key authentication is more secure than password authentication, so I have disabled password-based authentication for SSH on my ...
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4answers
1k views

Web browser password management security [duplicate]

Possible Duplicate: How are browser saved passwords vulnerable? How secure are the password managers that are built into modern web browsers? Currently I use lastpass plugin as I believed ...
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1answer
1k views

Why does Microsoft limit password length? [duplicate]

Possible Duplicate: Should I have a maximum password length? According to a recent TNW article: Microsoft doesn’t like long passwords. In fact, the software giant not only won’t let ...
6
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2answers
794 views

Production ready bcrypt implementation for .NET

Which, if any, .NET / C# bcrypt implementations are considered suitable for production environments? I have seen CryptSharp and BCrypt.Net mentioned in answers to other questions but without any ...
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4answers
199 views

Relationship of password strength and key strength

I have just started educating myself about cryptography, and while it is mostly making sense, a few things are still eluding me. One being: In systems that take a user's pass-word/-phrase in order to ...
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2answers
346 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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2answers
1k views

How do I block LinkedIn from extracting data from Microsoft Exchange Server?

LinkedIn now offers the ability to take a real user and password from the end user and connect to Exchange Server for the purpose of importing contacts into their system. (To do this yourself, click ...
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6answers
537 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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5answers
831 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 ...
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3answers
772 views

Tools helps: First time cracking passwords

I am trying to crack passwords on two Windows member servers (2003 and 2008). There is no Active Directory. Each user seems to use the same password across servers, workstations, etc. I have access to ...
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5answers
2k views

What password cracking software is commonly used?

I am curious to know how secure my passwords are. What password cracking software is commonly used? Preferably open source. EDIT: I am actually looking to crack my passwords used on services I ...
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9answers
1k views

How to easily remember lots of different passwords?

I know that you shouldn’t use the same password on every site. But, when you log into several dozen sites, keeping track of all the passwords can be pretty hard. What system do you recommend that ...
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3answers
496 views

Does it make any sense to alter a hashed password? [duplicate]

I've always wondered if it would make any sense to put fake characters into a hashed password? For example this is my password: 1234 and after hashing the password , this is the result: abcd Then ...
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3answers
291 views

Mutual authentication for humans

Is there any way for two people to securely authenticate each other without access to any special software (like PGP)? For example, when speaking over the phone or by sending SMSes to each other or ...
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3answers
2k views

Can password-protected zip files be broken without brute force?

You have a zip file that you created with 7z to password-protect it with AES 128. Can a smart adversary extract the data only through brute force, or is the file vulnerable to other attacks - such as, ...