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

learn more… | top users | synonyms (1)

10
votes
9answers
1k views

Why do we authenticate by prompting a user to enter both username and password? Does prompting the password only suffice?

I don't know why do we authenticate by prompting the user to enter both username and password. In my mental model, prompting password only suffices. The reason is as follows: Assume there are x ...
59
votes
3answers
14k views

How does Google Authenticator work?

Google Authenticator is an alternative to SMS for 2Step verification, installing an app on Android where the codes will be sent. It works without any connectivity; it even works on plane mode. This ...
26
votes
4answers
19k views

How do I secure my REST API?

In Detail here's the problem: I'm building an Android app, which consumes my REST API on the back-end. I need to build a Registration and Login API to begin with. After googling for a while, I feel ...
39
votes
9answers
3k views

Isn't OAuth, OpenID, Facebook Connect, and others crazy from a security standpoint?

I work with APIs all the time and I work with web developers who insist that OAuth, OpenID, etc are far superior than a home-brew method. Every site seems to be using these as well now for ease of use ...
21
votes
7answers
4k views

How to prevent cheating (extra votes) in online contests?

Mitigating Cheating & Voter Fraud in Online Contests… We run online contests of various sorts that involve users voting on entries (usually one vote per user per day). The prizes range from ...
22
votes
4answers
559 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 ...
20
votes
7answers
1k views

If I include a Forgot Password service, then what's the point of using a password?

I've implemented a Forgot Password service in the following way: User goes to login page, clicks on "Forgot password?" User is presented with a form that asks for their email address. Email is sent ...
18
votes
6answers
1k views

How to secure a WiFi network?

What do I have to do to secure a WiFi network? Is there any best practices? I have been recommended to use WPA2 encryption on the router, is that enough? What can I do to improve the security even ...
17
votes
9answers
3k 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 ...
13
votes
2answers
2k 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?
10
votes
4answers
434 views

How to protect against login CSRF?

http://seclab.stanford.edu/websec/csrf/csrf.pdf points out that most CSRF protection mechanisms fail to protect login forms. As http://stackoverflow.com/a/15350123/14731 explains: The ...
9
votes
2answers
11k views

How does ssh public key authentication work?

My basic understanding is this: The (connected to) server's sshd uses the public key to encrypt some message The client's ssh or ssh-agent decrypts it and sends something back (the message's ...
8
votes
3answers
931 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 ...
8
votes
4answers
6k views

Difference between authentication and identification [Crypto and Security perspective]

I am always confused by the way the word authentication is used in security literature (i.e., outside the crypto realm). Most of the time I understand that they are actually implying identification. ...
7
votes
6answers
2k views

Is denying login after incorrect attempts ineffective?

Generally denying logon attempts after X amounts of incorrect attempts for Y amount of tries is a very basic way to prevent bruteforce attempts or malicous logon attempts. Yet, surely doing this is ...
15
votes
5answers
60k views

Can someone steal money from my bank account if they know my IBAN and personal details?

To deposit money into your account, some websites require that you provide them with a lot of details about your bank account: name, complete address and IBAN which includes your account number and ...
4
votes
1answer
782 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 ...
34
votes
1answer
2k views

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 ...
19
votes
4answers
5k 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 ...
15
votes
6answers
944 views

Appropriate password requirements for a login (OpenID) service/provider/delegate/thing

This is with regards* to Stack Exchange's upcoming OpenID provider (and in particular, discussion about password requirements). Currently, password requirements are: Must contain 3 of: lower case ...
9
votes
3answers
2k 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 ...
8
votes
4answers
9k 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 ...
7
votes
1answer
512 views

Inconsistencies found in OpenID Provider's HTTP Headers. Which one is the most secure that I should imitate in my STS, and Relying Party?

I'm comparing the HTTP headers of the various providers (LiveID, Google, Yahoo, etc) and notice a broad inconsistency in implementation on the sign in page, sign out page, and subsequent pages. ...
3
votes
2answers
566 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 ...
7
votes
3answers
418 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 ...
6
votes
1answer
3k 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
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
5answers
624 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 ...
3
votes
2answers
307 views

Should the Keygen element be used to create a certificate for mutual auth TLS? What alternatives are there?

I'm interested in using mutual auth TLS to improve the security of my javascript based webservices . I've looked at the Keygen element and given all its issues, not sure if this can even be used for ...
10
votes
4answers
3k 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
1k 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 ...
7
votes
4answers
1k 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 ...
5
votes
2answers
654 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 ...
4
votes
1answer
340 views

How many authentication factors are there?

The three classes that we all know and love: Something you know. Something you have. Something you are. I've also seen references to "somewhere you are". Is this really a fourth factor? How many ...
4
votes
3answers
826 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 ...
2
votes
3answers
2k 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
3answers
223 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
175 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 ...
0
votes
2answers
129 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?
0
votes
2answers
218 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 ...
0
votes
1answer
173 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 ...
36
votes
5answers
7k 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 ...
29
votes
2answers
26k views

Token-based authentication - Securing the token

I have developed a backend REST API for a mobile app and I am now looking to implement token-based authentication for it to avoid having to prompt the user to login on every run of the app. What I ...
19
votes
3answers
5k 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 ...
36
votes
6answers
4k 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 ...
44
votes
7answers
5k views

Are passwordless SSH logins more secure?

I had a long discussion with my co-workers whether key-based SSH authentication (particularly for OpenSSH) is more secure than authentication using passwords. My co-workers always connect to servers ...
33
votes
11answers
5k views

Sending passwords to someone remotely

As someone who usually works with people in other countries it has always been a problem to send login information to each-other. For development login details like debug databases etc sure I can ...
32
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, ...
53
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 ...
44
votes
9answers
4k views

Generic error message for wrong password or username - is this really helpful?

It is really common (and I would say it is some kind of security basic) to not show on the login page if the username or the password was wrong when a user tries to log in. One should show a generic ...