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

learn more… | top users | synonyms

7
votes
2answers
597 views

How to proceed if a new hash algorithm for passwords is introduced?

I have an e-mail address at a certain institution. A few days ago they sent me an e-mail (in German), which I'd like to paraphrase without revealing the institution: Dear Madams and Sirs, a ...
0
votes
1answer
202 views

What type of attack should be used in order to pass this authentication

I am practicing the Astalavista Wargames and i came across this challenge. The question is: Bob wrote a piece of software but the password verification doesn't seem to work. You must find a way to log ...
2
votes
3answers
124 views

Is password authentication worse that signed messaging if done over SSL?

Let there is a public API: HTTP-based via SSL there are no browsers, just connections between custom written programs The first authentication scheme that came to my mind was... client signs their ...
3
votes
1answer
371 views

How genuine are password entropy calculations?

I apologise for perhaps the confusing title, I'll try and elaborate a little better. Many discussions I see surrounding password entropy focus on the specific context of the range of choices ...
4
votes
2answers
271 views

Passphrase using same word several times

I used a trivial 3-letter dictionary word five times in a row (smth similar to pwdpwdpwdpwdpwd), and am surprised to find my self in the list of hacked accounts in a penetration test using a ...
5
votes
1answer
485 views

How does SRP prevent man-in-middle attacks?

SRP is designed to resist both active and passive attacks, how does SRP prevent man-in-middle and packet modification attacks?
-1
votes
1answer
113 views

What makes EAP-SRP-256 better than SRP? [closed]

What is the advantage of the EAP-SRP protocol? Is it only used in wireless?
10
votes
3answers
1k views

What is the risk and mitigation of accidentally typing a YubiKey password in an open forum?

I have a YubiKey in my laptop (for testing) and accidentally broadcast my YubiKey password out to the Internet. Since this is only a test key, and has no access to anything of value, here are some ...
14
votes
3answers
6k views

Cracking MS-CACHE v2 hashes using GPU

As most people here will know, Windows caches domain/AD credentials in a format known as MS-Cache v2. Obviously, these would be excellent passwords to gain during a penetration test when local access ...
2
votes
1answer
209 views

How vulnerable are passphrases with grammatical structure?

Imagine I create a passphrase using random dictionary words but a common grammatical structure (eg: article, noun, verb, adjective, noun). Given a pretty small dictionary of 5000 words, how vulnerable ...
3
votes
1answer
469 views

Pure SRP authentication without TLS

IF using a SRP for client/server application authentication without TLS. Will it be vulnerable to man-in-middle attack, since if using SRP, the public info doesn't really useful to calculate the ...
22
votes
4answers
11k views

Demystifying Web Authentication (Stateless Session Cookies)

I'm currently researching user authentication protocols for a website I'm developing. I would like to create an authentication cookie so users can stay logged in between pages. Here is my first ...
3
votes
3answers
3k views

Email hacking myth

I never believed that some one can actually hack an email that easy. If someone hacks an email it means he actually hacked the server and he will gain access to many emails not to mine only. Anyway ...
1
vote
1answer
108 views

Error using ncrack

I am trying to run a ncrack command of the following format: ncrack -P filePath1 filePath2 --user user1, user2, user3 ipAddress:port and I get the following error; Does anybody know why I'm ...
-3
votes
2answers
517 views

Good Practice: Storing Passwords in general

I've got a totally theoretical question to you on today - what is the "best" practice for storing passwords? [Best in terms of security and performance] Usually, especially PHP-Developers tend to ...
3
votes
2answers
2k views

Why doesn't Microsoft implement salt on users passwords in Windows?

Pretty straightforward - So we use rainbow tables to get passwords of users out of hashes. So why won't Microsoft implement salt on the passwords in Windows to be hash(password+salt)? Won't this ...
1
vote
0answers
39 views

Database hash for password field [duplicate]

I'm using a mysql database and am looking for a cryptographic hash method for a password with salt added to it. What would be the best hash method for this problem?
2
votes
1answer
1k views

Using John the Ripper to crack SHA hash w/ partial knowledge

Group, I have a SHA1 hash that I would like to brute-force. I have knowledge of several characters before and after the password (ie, if the hash is derived from "xxxpasswordyyy", I know both xxx and ...
4
votes
4answers
611 views

Insecure to require numbers in passwords?

Earlier, I went to a site that required a number and special character, and it got me thinking – wouldn't that make the password easier to brute force? If you assume most passwords have around 12 ...
4
votes
1answer
289 views

Saved passwords (use case)

I have a program in which a user enters a password, and the user data is stored encrypted using AES-128. The data and passwords must be stored together. Both the data and the password are encrypted ...
-4
votes
1answer
429 views

Secure Web application Password vault/manager [duplicate]

I would like to build an open source online password vault which allows users to securely store their passwords, like Keepass or roboform, but where a user can access their passwords through a ...
3
votes
2answers
270 views

Fixing the high-bit problem in PHP's crypt() implementation

I'm working on a site that has to have compatibility with older versions of PHP, which suffer from a high-bit issue in the Blowfish crypt() implementation. Essentially, non-ASCII characters are not ...
8
votes
3answers
1k views

Encrypting user data using password and forgot my password

I am planning to do a web application which stores a lot of personal stuff (info, photos...). And to give users a sense of protection, I want to encrypt the data before storing it to the database. ...
1
vote
2answers
2k views

Is there a way to find out how long it takes John the Ripper to crack a particular password?

I am looking to test/demonstrate things like: when the supplied wordlist contains "abc123" and pw="abc123" then John cracks the pw in 1/2 a second... but if word list does not contain "abc123" John ...
3
votes
4answers
220 views

Securing opensource web application

I have an open source website. I need to add an admin section to the website which is accessible to only one person. To make it secure, I was thinking about providing a login page which checks if the ...
8
votes
2answers
480 views

Banning specific passwords?

There have been a couple of questions about enforcing good passwords, so I thought I'd add my own: In addition to enforcing a minimum Shannon entropy, would it generally be a good practice to ...
2
votes
2answers
277 views

What are my options for securely printing an OTP Scratchcard?

I want to print and distribute several One Time Passwords (OTPs) that can't be easily disclosed to a 3rd party in transit. (think the physical version of a TLS session for private secrets) To me ...
10
votes
3answers
390 views

If multi factor authentication is enabled, how should that affect self-service password reset?

Given that security is only as secure as its weakest link, suppose I have website with additional authentication enabled in any of these ways: (example, multiple conditions may be required) ...
0
votes
3answers
181 views

What day-to-day activities can compromise a person's information security [closed]

Recently a car was stopped next to me at the traffic lights. The driver had his phone connected to the car's bluetooth and the conversation could be heard by me crystal clear in the next car - the ...
5
votes
3answers
451 views

Use of rainbow tables with the NY Times hack?

The NY Times recently published a story about how they were hacked during a four month period. The hacks allegedly were carried out by part of the Chinese military. One part of the story that ...
9
votes
4answers
352 views

When changing a password using a WebPage, must the old password be entered on the same screen?

There is a convention to always prompt for the old password on the same page as the one where the old password is being changed as shown below. Is it acceptable from a security perspective to allow a ...
10
votes
7answers
2k views

Does adding dictionary words to passwords weaken them?

This might sound like a stupid question, but hear me out. If I'm encrypting my financial information and sensitive data via a program like TrueCrypt, the strength of the password is going to matter a ...
5
votes
3answers
1k views

Is using the same password for multiple TrueCrypted volumes safe?

I want to use TrueCrypt for encrypting multiple disk volumes. Assume I use the default cryptographic algoritm (AES) and hash algorithm (RIPEMD-160) and that nobody can get my passwords through ...
8
votes
3answers
799 views

Generating random passwords by clicking randomly on the keyboard?

How secure is it to generate random strings/passwords manually for different purposes by just clicking randomly on the keyboard ? I usually need random strings for salts and for passwords, and I ...
5
votes
2answers
4k views

Salted hashes vs HMAC?

Most of discussions involving access credentials include references to "hashing salted passwords". Is this another way to referring to the HMAC algorithm or a totally different operation? Different or ...
4
votes
2answers
965 views

How does processor architecture affect password hashing speed?

Does hashing speed vary significantly using different architectures (x86 vs ARM)? Scenario I am investigating the possibility of using a cluster of Raspberry Pi for cracking passwords hashed with ...
17
votes
5answers
1k views

From a security standpoint should users be asked to confirm their password when registering?

Is it advisable to have users re-type their password to confirm it's correct? On User Experience the general consensus seems to be no but I'm wondering if this has security ramifications? EDIT: my ...
5
votes
3answers
334 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 ...
7
votes
4answers
2k views

what are good requirements for a password

I'm making a website and I'm deciding on the password policy. What does make a good password? I really have no idea. I guess passwords should be at least 6 characters long. EDIT: are there any ...
17
votes
4answers
1k views

How to treat non-optional bad security questions?

Every once in a while I have to set up an account on a site that, while apparently at least not storing my password in plaintext, still force me to choose from a limited set of security questions that ...
11
votes
6answers
7k views

Are services like “LastPass” less secure, as they have all my passwords protected by a single password?

If the LastPass service has all my passwords and someone gets access to my LastPass password, this person will have access to all my passwords. Isn't that bad for security?
1
vote
1answer
1k views

Due to which reason might a windows 7 password been reset to empty?

A user reports on monday he cannot access his windows 7 account anymore due to a "wrong password", which perfectly worked on friday. It turns out the password has been reset to empty for that account. ...
4
votes
3answers
330 views

Completely mimimise the possibility of my web hosting account being hacked

I've just moved web hosting providers and I want a fresh, secure start. To a certain extent, I don't mind what I have to do I'm just fed up my account being hacked or infected. I just wondered how to ...
3
votes
1answer
1k views

I've heard that salt is not meant to be secret, but what if I made it secret? [duplicate]

Possible Duplicate: Password Hashing add salt + pepper or is salt enough? How to store salt? Ok I have been studying a lot about password hashing lately. And I have a few questions. So I ...
22
votes
3answers
2k views

Does overlaying the mouse on a virtual numeric keyboard really protect against keyloggers?

I just saw for the first time a new way to enter a password, at the Banque Postale (French Bank). You are given a virtual numeric keyboard and to type you can just leave the mouse cursor over a number ...
0
votes
1answer
2k views

Retrieving saved password from Firefox on Linux [closed]

I know there are ways to get the cookies from browsers in Windows and retrieve and decrypt saved passwords from them. Is there a similar way to do so on CentOS?
3
votes
2answers
274 views

is it easier to get the original password if you have multiple hashes of it?

Most users tipically use the same password for multiple applications. Let's say all of these applications hash the password in some way. Would it be easier for an attacker to get the original password ...
32
votes
4answers
2k views

If email is insecure, why do we use it for password resets?

I found myself telling a coworker today "Email is insecure, that's why we developed our secure report application." But then it struck me, Why is email considered insecure? If it is so insecure, why ...
3
votes
0answers
281 views

Can an attacker guess my password length from a hash? [duplicate]

Possible Duplicate: Possible to detect password length from hash? Is doubling your password adds more security? Considering I do not provide him any personal information relating to it, are ...
5
votes
1answer
2k views

Security of bcrypt/sha256 key used with AES to encrypt a file

I'm looking to encrypt files using secure hashing and encryption algorithms in Python. Having used bcrypt in the past, I decided to use it for my passphrase calculator, then pass the output through ...