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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27
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3answers
984 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 ...
12
votes
4answers
19k views

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 ...
10
votes
3answers
4k 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 ...
4
votes
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 ...
13
votes
5answers
1k 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 ...
10
votes
1answer
327 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 ...
3
votes
7answers
514 views

Is it wrong to root login with SSH?

I've long been under the impression that with unix, you should never login as root. Now I've started using Virtual Private Servers over at DigitalOcean, and some advice is to use SSH keys to login as ...
3
votes
2answers
809 views

User authentication + database encryption with same password

I'm working on a private project where I need to store a users financial data in a database. I'll encrypt this data using AES, and I'll be using scrypt to generate a AES ecnryption key from a more ...
2
votes
1answer
228 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 ...
17
votes
7answers
1k views

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)?
11
votes
4answers
589 views

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 ...
8
votes
3answers
561 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
votes
4answers
1k views

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
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 ...
7
votes
2answers
2k 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
votes
6answers
914 views

Isn't it less secure to use something you are for authentication?

I have to think of this everyday when I close the doors of the shop I work in: A year ago we used to close the shop and arm the alarm using a key fob. This means the worst case scenario was that I ...
6
votes
5answers
704 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
votes
1answer
121 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 ...
2
votes
3answers
3k 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 ...
1
vote
2answers
941 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?
1
vote
1answer
2k views

How to secure database table of users for an application?

I am working on a Windows application that utilizes a MySQL database for its user authentication and data storage. Within the application, the highest level of user (Administrator) can create and ...
0
votes
2answers
570 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: ...
10
votes
4answers
7k views

What are the disadvantages of single sign-on authentication?

We were discussing to implement single on in our web application,right now after analyzing we came to know that the following were the advantages of single sign on authentication. Advantages Users ...
8
votes
2answers
2k views

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
votes
4answers
2k views

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 ...
6
votes
2answers
942 views

Storing third-party auth info securely

Suppose there's a multi-user web application that requires access to user's mailbox (on third-party service, like gmail, etc.). This access needs to be persistent. Which means we'd have to store user ...
5
votes
2answers
4k views

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 ...
5
votes
3answers
2k views

storing the third party credentials in the database/some secure place

This question is about storing the third party credentials in the database/some secure place so that it can not be accessed by only authorized user. Our system connect to the third party system using ...
4
votes
2answers
1k 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 ...
3
votes
2answers
211 views

How does my bank knows my second and forth chars of my password [duplicate]

I see that the new login mechanism used by some banks in UK and also used by visa debit authentication is to ask for three random characters from your password at login (for example second, ninth and ...
3
votes
6answers
1k views

How to “demonstrate” man-in-the-middle attack?

I'm TAing a particular course on system security. A specific example is transitting the password in plain text when developing a web application (as part of a class project). Over the years a bunch ...
1
vote
3answers
292 views

Should I trust my bank after this [closed]

I have just discovered that I can login to my bank with passwords that is not mine. Example: My password is "1234" but I am authorized with all possible post characters. For example "12345" or ...
1
vote
3answers
238 views

Are subdomains a cure for phishing?

Seeing as phishing is getting more popular and users are becoming less concerned about security, I am trying to come up with a solution for a new site of mine that can stop phishers. For instance, any ...
1
vote
1answer
238 views

Securing communication

The problem: I have an open-source client (a Firefox add-on written in JavaScript) and a server containing somewhat sensible user information: username and user history (all from YouTube). The client ...
0
votes
2answers
269 views

Security concern to implement a web based remote desktop

I am implementing a web based remote desktop application.Through this application client can connect to the server and can access the server using JSP/Servlet Java robot class. I can configure the ...
42
votes
5answers
8k views

What are the downsides of BrowserID/Persona compared to OpenID/OAuth/Facebook?

Mozilla went live with a new service called BrowserID/Persona (announcement, background). It is intended to replace current single-sign-on solutions such as OpenID, OAuth and Facebook. One advantage ...
58
votes
6answers
7k views

Four-factor authentication

I'm sure you've all heard of two-factor/multi-factor authentication. Basically it comes down to these factors: Knowledge - something you know (e.g. password, PIN, pattern) Possession - something you ...
21
votes
3answers
6k views

What are the main advantages and disadvantages of webid compared to browserid?

What are the main advantages and disadvantages of webid compared to browserid? This question is inspired by this answer which got a number of upvotes despite being very vague on the topic of that ...
42
votes
6answers
7k views

Is using a public-key for logging in to SSH any better than saving a password?

Using a public/private key pair is fairly convenient for logging in to frequented hosts, but if I'm using a key pair with no password, is that any safer (or less safe) than a password? The security ...
38
votes
2answers
30k views

JSON Web Tokens (JWT) as user identification and authentication tokens

I'm implementing a REST service that requires authentication. I cannot store any per-user state (such as a randomly-generated token) because my service does not have direct access to a database, only ...
42
votes
4answers
13k views

How secure are the FIDO U2F tokens

Google and Yubico just announced the availability of cryptographic security tokens following the FIDO U2F specification. Is this just another 2FA option, or is this significantly better than solutions ...
39
votes
7answers
8k views

Why isn't open WiFi encrypted?

As far as I understand, WiFi networks that require no password send traffic through the air unencrypted. Those that require a password encrypt each connection uniquely, even if they're all using the ...
19
votes
5answers
4k views

How to uniquely identify users with the same external IP address?

I have created a login module on my website. I was able to deal with simple brute force attacks since I can identify the user based on username/email and throttle their login based on failed login ...
38
votes
6answers
2k views

Is the concept of Authenticated Anonymity possible?

Or is authentication essentially incompatible with anonymity? If we have the idea that authentication is proving that someone is who they say they are and anonymity is essentially having an unknown ...
33
votes
9answers
2k views

Use additional “password” in Referer to hide private site?

I have a private (= I'm the only user) site at example.com/private/. Nothing else is published at this host (it's my domain). I don't want anyone to know that there is anything at example.com, ...
22
votes
2answers
140k views

How do I clear cached credentials from my Windows Profile?

Windows seems to be saving my credentials for a variety of applications (terminal servers, etc) and I'd like to purge this data. How can I backup and purge this data?
55
votes
12answers
3k views

How do you log in from an unsecured computer?

Suppose that you are on a cybercafe, at a friend's home or at your work office, and you need to log in on a site, but you feel that the the computer can not be trusted (e.g. your friend isn't ...
42
votes
7answers
9k views

Should I change the default SSH port on linux servers?

Is there any advantage in changing the SSH port, I've seen people do that, but I can't seem to find the reason why. If you have a strong password and/or a certificate, is it useful for anything? ...
19
votes
5answers
1k views

Good session practices

What are some good practices for ensuring logins, session IDs and session content are secure for a website?
12
votes
4answers
7k views

avoid hitting DB to authenticate a user on EVERY request in stateless web app architecture?

Summary Once a user logs into a web site and his username/password credentials are verified and an active session is established, is it possible to avoid hitting the DB for each and every request ...