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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Good session practices

What are some good practices for ensuring logins, session IDs and session content are secure for a website?
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9answers
1k views

What's a good way to trigger a hidden 'distress signal' in instant messaging?

Here's the scenario: Alice and bob use Off-the-record messaging to communicate over IM. The have: Encryption Authentication Deniability Perfect forward secrecy They communicate after ...
19
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9answers
4k 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 ...
19
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8answers
9k views

Two-Step vs. Two-Factor Authentication - Is there a difference?

These days, there's pretty much three forms of authentication in general use on the web: Single-factor authentication, e.g.: PIN or password. Two-factor authentication, e.g.: Single-factor plus a ...
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4answers
7k views

Password resets - what practices should web services follow?

Many of you may have seen How Apple and Amazon Security Flaws Led to My Epic Hacking, where a Wired reporter's Amazon, Apple, Gmail, and Twitter accounts were successfully hacked. The hacker followed ...
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4answers
1k views

Is it a bad idea for an information holder to e-mail a user their password?

A couple of websites with which I'm registered have, after a period of inactivity on my part, each sent me an e-mail to remind me that I'm still registered. In each case, that e-mail has included my ...
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4answers
1k views

Biometric versus other Two Factor Authentication Mechanisms

Over the years biometrics is the go-to movie authentication mechanism, but in the real world I'm getting conflicting opinions about it. Everything I've learned shows that biometrics are flawed ...
19
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3answers
433 views

Isn't openid with http an issue?

Many openid enabled sites default to http identifiers, even if the openid provider supports https (such as myopenid.com). Does this pose a threat beside the identity being exposed? The second step of ...
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1answer
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Is it secure to connect to a remote Windows Server using Remote Desktop only?

I have a Windows Server that I login to from my home. I only use the pre-installed Remote Desktop. Is this a secure way to remote login or should I improve it in some way? If I should improve it, ...
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Why do we ask for a user's existing password when changing their password?

In a web applications context, when a user wants to change their current password, generally they would have to enter their current password first. However at this point, the user has already been ...
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2answers
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Why is it always `HASH( salt + password )` that we recommend?

Browsing over this site, many forums, online articles, there's always one specific way we're suggesting to store a password hash: function (salt, pass) { return ( StrongHash(salt + pass) ) } But ...
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4answers
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Should I implement incorrect password delay in a website or a webservice?

With arguments expressed in this answer, there is a few seconds delay between user enters an incorrect password and when he/she actually learns, that password was incorrect. This security solution is ...
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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 ...
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6answers
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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 ...
18
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3answers
27k views

What is single sign on versus federated login?

What is the difference between Federated Login and Single Sign On authentication methods?
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6answers
11k views

How to set up a single sign-on for multiple domains?

I've set up a single-sign-on for two of our sites that live on the same domain: a.domain.com and b.domain.com I did it through cookies, but they are domain-dependant. And - as it is written in the ...
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11answers
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2 factor authentication - cost effective solution for a web startup

My local bank uses a 2 factor authentication where customers key in password AND a One Time PIN delivered via SMS to mobile phone OR from a security token device. I am doing a web startup in the ...
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3answers
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Should I have a maximum password length?

I'm creating a webapp, and part of my authentication method is password length. Should I put one in place? (say, 50 characters?) Or should I just put a minimum length (Currently at 6). Are there ...
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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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6answers
1k 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 ...
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4answers
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why a client authentication is not commonly performed in the TLS protocol?

Is there any reason for this other than key/certificate management on the client-side?
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3answers
1k views

Multi factor authentication on Ubuntu workstations, where to start?

Is it possible to have Ubuntu users log in with multi-factor authentication? I was thinking of a combination of pass(word|code) and smartcard (with screen locks when for example smart-card is removed) ...
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2answers
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Is it okay to sign a PGP key without an IRL meeting?

[PGP] can get paralyzed by excessive analness. — Phil Zimmermann Preamble I am in the process of building my own web of trust. That is, I want people (PGP users…) to be—fairly—sure that, by ...
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1answer
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Configure SSL Mutual (Two-way) Authentication

A lot of tutorials, a lot of pages, a lot of question and they differ in implementation of this issue "Configure SSL Mutual (Two-way) Authentication". I have to do it with Linux, and I don't know from ...
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9answers
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is there a safe way to login to my gmail account from a public pc?

Sometimes i need to use a public pc to access my gmail account, is there a safe way to login and keep my password safe in case there was a keylogger or a trojan on that pc? are there tools that could ...
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5answers
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How many Stack Exchange logins should I have?

On Stack Exchange's Add a login page, one can add logins with Google, Facebook, Yahoo, etc. How many logins should I have to provide the least chance of a hacker gaining access to my Stack Exchange ...
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2answers
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Role Based Authorization vs. Claim Based Authorization

What is the difference between "role based authorization" and "claim based authorization"? Under which circumstances would it be appropriate to implement each of these authorization models?
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2answers
475 views

Which factors should I consider for devices that accept handwritten digital signatures?

These days many locations ask you to give your signature on a digital signature pad/device. As I am situated in Europe, the EU directive 1999/93/EC seems to regulate it. From what I have found out ...
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5answers
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Does two factor authentication prevent social engineering attacks

After reading this article from symantec I got to think how much all these social engineering techniques rely on the authentication system of users, a password. Considering three different additional ...
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3answers
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Multi-tenancy, SSL Certificates, and Subject Alternative Name

The X509 specification allows a CA to issue a single certificate for multiple hostnames, by using the "Subject Alternative Name" extension. From the spec: The subject alternative name ...
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5answers
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How should passwords be stored if they must be recoverable?

By "encrypting" passwords you are violating CWE-257: Storing Passwords in a Recoverable Format. But this is exactly what the French government wants. They want to be able to obtain the passwords of ...
15
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5answers
975 views

Safe way to authenticate (multi-factor authentication?) while being monitored?

(I'm trying for a bit more precise answer, particularly with regard to multi-factor authentication, than I received for "Safe way to use a computer that has spyware/keylogger installed?" on SU.) ...
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3answers
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Computationally simple, lightweight replacement for SSL/TLS

Target hardware is a rather low-powered MCU (ARM Cortex-M3 @72MHz, with just about 64KB SRAM and 256KB flash), so walking the thin line here. My board does have ethernet, and I will eventually get ...
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4answers
872 views

Does two-factor authentication reduce the need for a long password?

I've recently enabled 2-factor auth on a number of web apps, mostly using Google Authenticator. Does this mean that the importance of a strong password on each site is reduced? I would prefer to use ...
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6answers
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How to implement multi factor authentication using a token generator?

I'd like to implement multi factor authentication on a few projects. Now the first factor would be username and password, for the second factor I would like to use a token generator. These tokens ...
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4answers
547 views

Why aren't digital signatures the standard way to authenticate web clients?

The web is a mess of incompatible cookie schemes, asinine requirements ("your password must contain letters, numbers, and at least one symbol from !()-_., and must begin with a letter, and once you ...
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4answers
316 views

Are malicious relying parties able to abuse OpenID logins?

if I logon with OpenID into a website (crafted by attackers/hackers) I want to know how much damage can they do to me? Are they able to steal my contact info, name, etc (assuming I'm using Gmail ...
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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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6answers
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Is This Login Security Enough?

I'm coming up with my next login system for admins of an ecommerce website to have login form is SSL secured password is converted to sha256 before being transmitted (bcrypt is too slow still for ...
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3answers
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Is the Facebook login form using SSL without https in the URL?

If I go to http://facebook.com, I am not redirected to https://www.facebook.com. If it doesn't have https in the URL, can the login be secure? Usually I am redirected to an https page on other sites? ...
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2answers
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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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6answers
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Additional security benefits from Multi-Factor Authentication?

Does multi-factor authentication provide any additional security benefits on top of doing a better job at correctly identifying and authenticating users compared to single factor authentication? In ...
14
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5answers
2k views

What is the difference between login throttling and temporary account lockout? [closed]

I am currently working on the redesign of a login page. I have initially suggested that login be throttled whereby pauses (incremental - in number of seconds) are introduced between each failed login ...
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3answers
811 views

What can I do if my bank thinks my date of birth is “known only to me”?

My bank has recently replaced passwords with occasionally asking me information that is "known only to me". Such information includes my date of birth, postcode, and my mother’s maiden name. ...
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4answers
750 views

Entering passwords at public computers

Sometimes it happens that I have to access my email or some other web service from public machines. Are there any options to make it secure or at least reduce risks to acceptable levels? I am most ...
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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4answers
4k views

Three-Factor Authentication for Windows

This HowToGeek article... http://www.howtogeek.com/67556/how-to-unlock-your-pc-by-being-nearby-with-a-bluetooth-phone/ ...got me thinking. Is there any software (or combination of software) that ...
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2answers
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Hiding user account names from unauthenticated RDP sessions

This is for a Windows 7 Ultimate system, which is not a member of a domain. When I log into the system locally, I am required to either manually enter my user ID or authenticate with biometrics. The ...
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3answers
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Should security question answers be case-sensitive?

Question In the case of security questions being used to reset an account password, what is considered best practice for handling case-sensitivity on the security question answers? Scenario An ...
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2answers
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Encryption strategies for multi users access in production systems

I am pretty unknown to encryption strategies in production environments. So my concern is to find a solution how to strongly encrypt data, but make it available to multiple users with different keys. ...