Authentication - establishing the authenticity of a person or other entity. Not to be confused with authorization - defining access rights to resources.

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HTTP Basic auth password storage more secure than Digest auth

If you are using SSL already, it appears Basic auth is the way to go since you can perform bcrypt with the password when you store it in the database, where as Digest auth only allows md5. As we know, ...
19
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4answers
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What is the difference between authenticity and non-repudiation?

I'm new to infosec and doing some reading. Not surprisingly one starting point was wikipedia. In this article, authenticity and non-repudiation are listed as 2 separate 'Basic concepts'. My ...
19
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5answers
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Why is client-side hashing of a password so uncommon?

There are very few websites that hash the users password before submitting it to the server. Javascript doesnt even have support for SHA or other algorithms. But I can think of quite a few advantages, ...
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4answers
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How to implement non-password authentication in a web site

In an answer to this question about pw reset, D.W. says: Lastly, consider non-password authentication. Passwords have many problems as an authentication mechanism, and you might consider other ...
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3answers
6k views

Is it possible to use a GPG or SSH key for web based authentication in a secure fashion?

Let's say hypothetically I am writing a web application targeting technically inclined, security-conscious users who have no problems generating and using GPG or SSH keys. Is it possible to use said ...
26
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2answers
7k views

Is there a standard for printing a public key as a barcode?

Is there a standard for storing a public key printed on paper? Say, I want to hand out business cards with my public key pre-printed on them at a key signing party to help build the web of trust. My ...
22
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4answers
2k views

How does using OpenID affect webapp security?

Using OpenID for authenticating users grows in popularity and, in fact, makes a webapp easier to use. But what are the security considerations one should bear in mind when deciding whether to ...
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10answers
6k views

Can IP address be a component of 2-factor authentication?

I have a bunch of Linux machines that I wish to administer over the Internet. I currently use SSH keys, but have been advised to use 2-factor authentication. SSH Keys are something you know. Is an IP ...
14
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6answers
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Securing an API for mobile access

I've built a nice REST/JSON API that is used by other companies (our clients) as a B2B service. Each of our clients has a username/password pair, and we also do HTTPS and validate the source IP of ...
12
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3answers
596 views

Is it inconsistent to tell users to “not click on password links in email”, and requiring clicks on “forgot password” links?

On one hand, IT Security shops have been telling users to not click on links in email because they can do damage to your computer, or phish your personal information. Many of those issues are ...
9
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3answers
2k views

Verify Login and Encrypt with PBKDF2

I'm writing a desktop application where I'm using PBKDF2 to generate an encryption key to AES-128 encrypt the config file. The config file contains a crypo-random key that's been used to encrypt the ...
51
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1answer
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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 ...
22
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4answers
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How secure is Windows 8's Picture Password login?

The final Windows 8 build has been released to manufacturing. One of the new features of Windows 8 is "Picture Password", where the end user logs on to Windows by clicking a specific pattern on the ...
18
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6answers
8k views

How to verify that someone is who they say they are online?

I am working on an online job application web app and the question has come up about how we will verify that someone submitting an application is who they say they are. For example, we don't want ...
15
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2answers
2k views

Password and Generated number - How does it work?

In my company, they don't allow accessing the company email or servers from outside the company network. To access the email from outside the network, you have to use: Username, password and a number ...
14
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2answers
3k views

What are the most common password salting methods?

I learned that the Sun guys used the login name as salt for password hashing. Is this a common approach? What are the most common salt values?
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3answers
2k views

How to replace an old password hashing method with a newer one in software? [duplicate]

The software that our company builds just went through a security audit. The auditors flagged our use of MD5 for hashing passwords that users can set if they want a password on their files. Having ...
27
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3answers
1k views

What is this authentication method/approach called?

Background: I want to implement something like this in our websites, and I'm looking for advice and possibly APIs that allow this out of the box rather than re-inventing the wheel, but I can't even ...
11
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6answers
6k views

Is tokenless (specifically SMS) 2FA a security compromise over OTP tokens?

I've been looking into the various pros/cons of tokenless (particularly SMS based) and traditional token based two-factor authentication (think RSA SecurID). After doing some research, I think I have ...
10
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3answers
6k views

How does an SSL server prove its identity?

This document says that a challenge response authentication proves the servers identity. But is a man in the middle attack still possible if the client does not verify domain name ? Please help me ...
10
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1answer
434 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 ...
7
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3answers
2k views

Is it possible to have authentication without state

In order to login to most websites you need a username and password which is often stored in a SQL database. You are storing per-user information that can change, this is state. Can you prove that ...
6
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7answers
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How can I best manage root passwords for many servers?

Lets say I have two racks with about 40 nix servers in them. I don't want to set all of the root user passwords all the same do I? If not how do you manage and keep up with all of the passwords? Is ...
4
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1answer
1k views

Blackberry + RIM Bluetooth-based Smart Card Reader

Has anyone used this Bluetooth based smartcard reader? (scroll to bottom) If so, what are your experiences with it? Can you tell me if it's possible to require only the presence of the card + card ...
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3answers
318 views

How to (further) ensure SSH security?

I set up my Linux Ubuntu machine as an SSH server through no-ip.com and it works great. Recently I discovered the command, sudo lastb -ad -F -w which outputs a log of the most recent failed SSH ...
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7answers
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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)?
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5answers
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NFC contactless payment security

This is really bugging me. Up until recently debit cards with an electronic chip were the most popular electronic form of payment available in Poland (I'd wager that in other European countries as ...
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5answers
2k views

Is there any reason to show the same message for invalid username as password?

I've seen a security question/requirement that a website login return the same error message for invalid password as for non-existent user. The idea being that this it makes it impossible to discover ...
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2answers
3k views

ssh public/private key pair

I am having problems understanding how ssh really works. I know it uses a public key cryptography to encrypt messages. However, I can ssh to a server without first generating a public/private key pair ...
6
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3answers
937 views

Two-Factor Authentication: When is it worth it?

I was reading this article, and it triggered the question: Why not use two factor authentication? In his case, it both possibilities were enabled anyway, so this looks to me like it's two attack ...
3
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1answer
383 views

Why recommend “letters, numbers, and special characters” in a User ID?

Why do some sites recommend "letters, numbers, and special characters" in a username or User ID? When creating a User ID at the www.discovercard.com website, the "User ID Strength" indicator meter ...
10
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2answers
1k views

My bank makes me enter my password using the mouse. What's up with that?

Internet banking login process for Westpac requires user to enter the password using the mouse. It's annoying, what's up with that? Is it just to try and stop keyloggers on public computers or is ...
9
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3answers
638 views

Does Gmail 2-factor auth increase security on smartphones?

So I have enabled 2-factor authentication on Gmail, which means that if I log in on a new machine, it sends a token to my phone. Now, if I access Gmail from my phone, it seems like I have only one ...
7
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4answers
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How to prove Bob has received Alice message

I have read up on Digital signature and it is stated that it provides non-repudation. Assuming Alice signs the message using her private key and sends it to Bob, Bob can use Alice's public key to ...
7
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2answers
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When using symmetric key encryption, do we need to sign?

Say we're using a shared key between two parties, that has been distributed using public key encryption, is it still necessary to sign any data that's encrypted using the shared key? Or is it enough ...
7
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1answer
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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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5answers
753 views

Should a closed source website keep a secret key in its source?

Various APIs (such as Facebook or Amazon S3) require a secret key to authenticate access to the service. Obviously, if source code is public, the key should not be in the source! What about for a ...
5
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1answer
296 views

Security protocol for NFC stickers/cards

Lets say I'm using NFC cards for access control. NFC cards/stickers are easily readable and writable, so my worry is that the data on them could easily be cloned onto another card/sticker and bypass ...
4
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2answers
2k views

Is HTTP Digest + MD5 still an alternative to consume my own api?

I'm reading a lot about implementing security constraints to a REST API. There are a lot of methods, some better than others for 3party applications or to consume my own API. HTTP Basic + TLS (with ...
2
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3answers
3k views

Determining the accuracy of a biometric system

How is the accuracy of a biometric security system (its ability to minimize false acceptance rate and false rejection rate) determined?
2
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2answers
145 views

Single-use password as the default authentication method?

The crazy password requirements (joke1, joke2) lead me to a situation where there is no way for me to memorize the passwords to the several sites that make those requirements. The result is that ...
2
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3answers
4k views

Dealing with untrusted administrators in a Windows domain

I'm providing consultation to a company, where they have domain-joined Windows workstations. One basic requirement is that they don't want anyone (including the an administrator) to be able to login ...
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5answers
738 views

VPN Authentication over WiFi — Is it secure?

Count this question as part of my ignorance on how authentication scheme is done on your typical VPN session. But here goes: We often advise the security-conscious user that if one must use an ...
0
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2answers
962 views

Generating authentication token from PHP sessions

I have a traditional PHP site which uses sessions. I've developed a real-time app in nodejs and wish to authenticate users here based on their PHP session. The procedure would go something like this: ...
12
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2answers
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Benefits and drawbacks of giving an Administrator two accounts for elevated rights and another for daily use, such as email

Microsoft has long promoted the need to separate administrative accounts from regular use accounts, as shown with this guidance MSFT even went to far as create ADMINSDUser rights to put ...
8
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4answers
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How to protect ftp account information in the source code of a program

I wrote a game which stores high score information on an ftp server. In the the source code I need to write out the ftp link with the account name and password in it. For example: url = new URL("ftp:...
6
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5answers
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What is the most credible timestamp I can create for a digital file?

Is it possible to create a timestamp that is so hard to fake, that it could be used as proof or simply strong evidence in a court of law, that something was not created after a certain point in time? ...
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278 views

Protection of eduroam credentials

Recently my educational institution officially switched over from the their own wireless network to eduroam. If I understand correctly from the FAQ, credential authentication is performed on the ...
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3answers
332 views

How bad is exposing valid user names?

Today like many other times in the past, signed for a new service and got a common error message: Your user name or password is invalid This time I am wondering how useful it is to notify "...
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Disabling authentication via DSA keys in OpenSSH?

How can I disable DSA and ECDSA authentication on my server with OpenSSH 5.9? Sifting through the documentation material and doing a web search didn't yield any results - only an old bug report for ...