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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Are login “certificates” more secure than standard username + password authentication?

I just opened a new bank account which comes with internet banking. Unlike the others I have used so far, this one requires a personal certificate (a .p12 file stored on my computer) + password for ...
21
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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 ...
21
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3answers
3k views

How is Google Chrome managing authentication to sites?

In Chrome, every tab is its own process. Yet, logging in to a site, say, Facebook, persists across tabs. For that matter, in many cases, it persists across OS reboots. This seems inherently very very ...
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3answers
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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 ...
21
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2answers
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Sending temp password when users first registered - is that good for anything?

One of our clients has sent us a list of security requirements. One of them was that registration does not including setting a password - once complete, a temp password is sent to the user, and the ...
20
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8answers
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On two-step login forms, why is it the login name and not the password that's asked first?

There are several login forms (e.g. Google's) on the internet where you first enter your login name and then, once that's submitted, you get to enter your password. One of the advantages of this is, ...
20
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6answers
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Web authentication - password vs key file

There is a corporate web mail site (PHP + MySQL) for limited numbers of users who are employees of a company working remotely with the corporate web portal. Each user has a login and password. I'm ...
20
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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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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 ...
20
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5answers
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Why do some websites and programs restrict password characteristics?

There are some websites and even programs that I use that have rediculous password restrictions. Lots of forums for instance restrict passwords to ~32 characters. Others enforce a restricted charset. ...
20
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4answers
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Google Account: implications of using application-specific passwords

In the wake of the recent Mat Honan story I decided to try out two-factor authentication on my Google account. But in order to keep using it with Exchange, the Android OS, Google Talk and Google ...
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4answers
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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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Are reCAPTCHA enough to prevent brute-force password guesses?

I was wondering if reCAPTCHA were strong enough to prevent BruteForce from bots or if I needed to add more security, such as sending a unique mail to the user every 5 tries that someone try to log on ...
20
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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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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 ...
20
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2answers
1k views

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 ...
20
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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 ...
20
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3answers
269 views

What precautions should I take when creating users that will be used by applications and not by people?

I have some applications that need to access to a webservices bus. Own applications that access to the bus authenticate using a webservice on that bus but in this case I need that third party ...
20
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1answer
2k views

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, ...
19
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4answers
3k views

Why use a Smartcard for (Two Factor) Auth instead of another medium?

I recently installed Bitlocker on my Windows 8.1 machine, using only a password. I was thinking of getting something other than just a password for my storage drive, something physical, like a USB, SD ...
19
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5answers
2k views

Good session practices

What are some good practices for ensuring logins, session IDs and session content are secure for a website?
19
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2answers
5k views

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 ...
19
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5answers
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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 ...
19
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4answers
9k 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 ...
19
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2answers
8k views

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?
19
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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
443 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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6answers
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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 ...
18
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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 ...
18
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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 ...
18
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6answers
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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 ...
18
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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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6answers
13k 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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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 ...
17
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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)?
17
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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 ...
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3answers
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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) ...
16
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7answers
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Forgotten password or reset link, which is more secure to email?

I originally posted this as a reply here in this thread but didn't get much feedback on it, and now I'm curious as to what others think is the best approach, or if there is any difference between the ...
16
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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 ...
16
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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 ...
16
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5answers
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What is the difference between login throttling and temporary account lockout?

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 ...
16
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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 ...
16
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4answers
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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 ...
16
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4answers
358 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 ...
16
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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 ...
16
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2answers
548 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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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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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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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.) ...
15
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2answers
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Secure communication between applications using SSL Certificates

I am looking for a way how to secure communication between our applications. There is a "server" application listening on some TCP port and "client" application which is communicating with the ...