Single password versus password and username [closed] - authentication

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What security benefits password and username provides over just single password as login?
If username must be unique, then other users cannot have that username and user can be mapped to user account with that id. When attacker brute forces against username and password, it same as attacker would brute force against single password. But with single password attacker can try to access all accounts with same password brute forcing.
After you are logged to application, you session is authenticated with single password, which is session id. So attacker could try to login to all accounts by bruteforcing session ids. Of course session ids are usually very long and therefor very hard to bruteforce.
What if application generates automatically password tokens and adds always unique prefix (length of prefix is stored in database) for passwords that what is mapped to specific user. So that password is actually combination of username and password, but user doesn't know that? Will that kind of setup have same security as username and password system?

When thinking about a single password approach I can see a number of possible issues, for instance if you are allowing users to set their own passwords then just having password as login credentials opens up your application to massive security flaws.
The most common scenario is that a user will sign up and use a password such as their name, or some other commonly used insecure password thus making it easy to brute force.
Also consider the fact that as the number of users grows the number of acceptable passwords to access your site also grows which makes it easier for brute force attacks to work. Even with auto generated passwords this is the largest issue I would be concerned with.
Thirdly, I come along and try sign up to your site, I type in my password "Bob1" now what if another user has entered the password "Bob1" ? Do you inform me that password exists? Two users cant log into distinct accounts with the same password.
The main issue here to consider though is that users are used to typing a username and password. I personally wouldnt want to sign up to a website where I just have to type in a password, and most importantly I wouldnt want to use a web site where my password is auto generated and hard to remember.
If you are concerned about security (as you should be) then I suggest enforcing strict password rules (expiry time, length, content) and educating your users about the flaws of insecure passwords. On creation of the password you can check it doesnt match any info the user has entered such as name/ date of birth etc.
Overall I would say username / password combo is better than single password for both security and usability reasons.
Also see http://xkcd.com/936/

If you use only password, then someone could type a word like 'helloworld' and log in to a random account.
Coz there would be someone who is using this password.
There are many who would use familiar phrase as password. Its users convinence.
Such type of loophole dosent exist in username-password combination.

Related

Alternative way to reset password

I want to let user to reset password in case he/she forgot his/her password without sending reset code to his/her mail box. Actually I don't want to use emailing reset password system.
Is there any way to let user reset his/her password without using email in secure way?
Is 'security question' using safe?
Or what is safe to use?
The safety of the secure question will depend on the difficulty of the question itself. If you don't want to use the mail() function then you can try either of the following:
You can send an OTP to his registered phone number.
You can use more than 1 secure question to identify the user and then allow him to reset the password. But make sure that the standard of the question is high.
For eg., avoid easy questions like name of your first school, name of the birthplace, etc. These questions can easily be answered by any other person close to the user.
Try questions like- What is the name of the city where you got lost?, What is the name of the teacher who gave you your first A?, etc.
This will be safe as well as help you avoid mail() function.
Safety can be improved with
OTP on mobile.
asking user to validate their personal information like:
email address,
last name,
date Of Birth,
last 4 digits of social security Number. etc..
two layer Reset. send two different codes to (primary and secondary/mail and mobile) and verify both of them.
if you have users registered mobile number. You can use One time password to authenticate users identity before letting him reset the password.

phpBB Password Authentication on Custom Site

I have been looking for the past few hours on how to user the phpBB login script on a custom site. I think I'm just not searching for the right things.
A while ago, I created a phpBB site and have over 900 members registered through phpBB. I am currently face-lifting this site and redoing the user registration along with all of the other custom code I have.
My problem is, I want the users to be able to log in as usual, though I want to input them into my new database so everything can run smoothly. I mainly need their username, password and old ID#, but I don't know how to use phpBB's password authentication or where to find it
The statement needs to look something like this:
On Login, grab username and password variables:
if the username is not in MY database, check phpBB database.
If the username is in phpBB database, check to see if the password is correct **(This is the part I don't know how to do)**
If the password is correct, input the username, user ID and the password (encrypted my way) into MY database
Login
If the password is incorrect - error
if the username is NOT in phpBB database - continue
if the username is not in MY database - input username and encrypted pass into my DB
login
Where can I find a script to authenticate the phpBB user's passwords? I don't care how the script is done, I know that's a secret, I just need to be able to authenticate passwords so that I can make sure it's the same user
I do have access to the phpBB database, I just need a way to authenticate their password
I would rather delete the quesion, but here's the answer:
Check here: http://sunnyis.me/blog/secure-passwords/
and when you download the PasswordHash.php, change all of the $P$ to $H$. It will work. Strange how it creates a password, every time it creates, it's different. But the CHECK part of it makes sure it checks it correctly, no matter what hashed pass it creates.

Is there a safe way to send a user their password in clear text via email?

If I understand correctly, the biggest problem with sending a password via email is that it requires the password to be stored in clear text in the database. If the DB is compromised, the attackers will gain access to all accounts.
Is there a workaround for this problem?
How can one make sending a user their password via email as safe as possible?
The simple answer is: don't. If you think your database is insecure, an email is far, far less.
If you mean that you want to send them their password when they register, then you could do that before you store it in the database.
If you mean after they have registered, the only option is to store in plaintext (again, don't do this) or make a new, random password and send them that. It is impossible to get their password from the hash, which is why it makes the password storage safer. The best option is to generate a new (temporary) password you send them, or a token giving them access to a password change system.
You may want to consider a good hashing algorithm like BCrypt that includes a salt.
I don't know if my suggestion is feasible for your scenario, but you should better keep the data hashed or encrypted and send password reset links instead of plain-text passwords.
The moment the password is in cleartext in the email, it is inherently insecure.
As such, there is no safe way to send a password in cleartext safely.
You should not be storing passwords in cleartext in your database - you should be using salted hashes. When the user enters their password, you hash it with the salt and compare to the stored hash.
When people forget their password, instead of sending passwords by email, you should send reset links backed up by expiring tokens. These would generate a temporary new password (that would expire within minutes).
You should be hashing all passwords in your database.
sha1($_POST['password'].$salt.$username);
In the case of a lost password
A user requests a password reset link, which contains a hash generated in the "user_meta" table. When the user recieves this link, the hash is compared to that in the database, and the user will be able to UPDATE their current password with a new password.
The PTXT of the password is never reveiled.
You only compare hashes.
Yes, there is a common workaround.
Assuming that you have your users in your database.
You send the "password reset link" containing some "key" information, like a guid. An example link is a form:
http://your.site.com/setpassword?id=5b070092-4be8-4f4d-9952-1b915837d10f
In your database you store the mapping between sent guids and emails.
When someone opens your link, you check your database and you can find out who asks for the page - because any valid guid maps to an email. You can then safely let the user change his/her password assuming their email is not compromised.
When it's about to store the password, you never store it in plain text, you always hash passwords, using additional random salt to make the dictionary attack more difficult when someone breaks into your database.
There is a workaround which is less secure than a password reset but works if it is a requirement that users are sent a password, not a reset link.
What you do is you generate a new password that contains sufficient randomness to be very hard to guess, but is also formatted in a way that it is easy for them to remember and read out (say over the phone).
Something like: xyz-xyz-xyz-nnnn where xyz is an easy-to-spell but uncommon word and nnnn is a four digit number.
Then set it up so that this is a temporary password that needs to be changed on first login.
Set the password using the same logic you would use to set a normal password, so that it is correctly salted and hashed, and then send the password plaintext via email, like so.
Dear FirstName LastName,
You requested we reset your password.
Your new password is:
insipid-mirth-nonplus-9174
You will be able to log into the system once using this password, then you will need to enter a new password.
Important Caveats
This system has some serious vulnerabilities which make it unsuitable for websites where data security is crucial. There are more than these, but these are the ones I know/can think of:
Unlike systems which use a password reset link, this system could be used to lock someone out of the system (assuming you use it as is) unless you either require someone to fill out identifiable information before issuing the password reset, or send a "are you sure you want to reset your password?" email first. This would entail them clicking on a link with a GUID that goes to the server; at that point they may as well be sent to the password reset form anyway.
Since the password is being sent plain text via email, there is a danger it can be intercepted and the password can be used. Although to be fair this is not that much different than the risk of sending a password reset link.
If you ignore the risks in step #1 and you don't use a sufficiently random way of generating passwords (say you use a word list of fewer than 1000 items), someone who has hacked into your server will be able to retrieve the salted password hash and then write an algorithm that generates all possible passwords and checks them against the hashed password. Not as much of a problem if you use a cryptographically complex hashing algorithm.
If you want to send password to user via Email in cleartext and want to store those password into database as hash or any other format . It will be possible.......
Just you will have to follow some simple way....
1 .you will have to take those password as variable which will send from user.
2. When you store database then just convert it as you wishes format.
3. But when you send those to user by mail , That time just sent those variable password...
I think it will be helpful to build your concept about WAY.......

Implement password recovery best practice

I want to to implement password recovery in my web application.
I'd like to avoid using secret questions.
I could just send the password by e-mail but I think it would be risky.
Maybe I could generate a new temporary random password and send it by e-mail but I think it is as risky as the above point.
Can I send a url by e-mail for example http://example.com/token=xxxx
where xxxx is a random token associated with the user. So when the user navigates to that url he/she can reset the password.
When I was in the Air Force the security rule we had was: When setting or resetting passwords, do not send the user id and the password in the same email. That way, if someone is intercepting emails snooping for passwords, he has to successfully intercept BOTH emails, and be able to connect them, to breach security.
I've seen a lot of sites that use the "go to this URL to reset your password". Maybe I'm missing something -- I don't claim to be a security expert -- but I don't see how that is any more secure than just inventing a new, temporary password and sending it. If a hacker intercepts the email, why can't he go to that link and see the new password as well as the legitimate user could? It looks to me like extra hassle for the user with no security gain.
By the way, congratulations on NOT using security questions. The logic of this device escapes me. Since the dawn of computer security we have been telling people, "DON'T make a password that is information about yourself that a hacker could discover or guess, like the name of your high school, or your favorite color. A hacker might be able to look up the name of your high school, or even if they don't know you or know anything about you, if you still live near where you went to school they might get it by tryinging local schools until they hit it. There are a small number of likely favorite colors so a hacker could guess that. Etc. Instead, a password should be a meaningless combination of letters, digits, and punctuation." But now we also tell them, "But! If you have a difficult time remembering that meaningless combination of letters, digits, and punctuation, no problem! Take some information about yourself that you can easily remember -- like the name of your high school, or your favorite color -- and you can use that as the answer to a 'security question', that is, as an alternative password."
Indeed, security questions make it even easier for the hacker than if you just chose a bad password to begin with. At least if you just used a piece of personal information for your password, a hacker wouldn't necessarily know what piece of personal information you used. Did you use the name of your dog? Your birth date? Your favorite ice cream flavor? He'd have to try all of them. But with security questions, we tell the hacker exactly what piece of personal information you used as a password!
Instead of using security questions, why don't we just say, "In case you forget your password, it is displayed on the bottom of the screen. If you're trying to hack in to someone else's account, you are absolutely forbidden from scrolling down." It would be only slightly less secure.
Lest you wonder, when sites ask me for the city where I was born or the manufacturer of my first car, I do not give an actual answer tot he question. I give a meaningless password.
</rant>
First off, do not store a plain-text copy of the user's password, or even an encrypted version. You want to only ever keep a hashed copy of the user's password.
As for recover solutions, I find that the recovery link to change the user's password is the best solution in my experience. It will probably be a bit more convenient for the user, while being largely the same from a security point of view as sending a new random password to be changed after next login. I'd still recommend having the recovery url expire after a reasonable short period of time, as well as only being usable a single time.
Hard to say what you should do, as pretty much any solution to this problem will weaken security. Unless maybe you want to investigate sending an SMS, callback verification, one-time password generators, or other such schemes that take password recovery to a different medium.
However, what you should not do:
Send the password - because after all, as has already been mentioned, you don't have it.
Generate a new temporary password - not only is this as insecure as sending the password, it also leads to the possibility of a denial of service attack. I can go to the site, pretend to be you, request a new password and then (if you haven't checked your email) you can't log in, don't know why and have to request a new new password ...
The token is probably the way to go. Receiving it notifies a forgotten password request, but doesn't take any action unless you confirm. You would also make it a one-time token with a relatively short expiry time to limit risk.
Of course, a lot depends on the application. Obviously protecting financial and other sensitive information is more critical than preventing your account being hacked on mytwitteringfacetube.com, because while it's inconvenient, if someone wants to steal someone's identity on a social network site, they can just open their own account and masquerade with stolen information anyway.
Obviously, you can't send the original password by email, because you're not storing it (right?!). Sending a temporary password (that must be changed, because it only works for one login), and a link to reset the password are equivalent from a security point of view.
I don't unnderstand the attitude towards the secret question method. It's not like I am going to make my password "BlueHouse" and then make my security question "What are your two favorite things?" and the answer "Blue and Houses". The security question is not the magic key to get the actual password. It's usually a way to get a new password sent to the email address on file. I don't know how else you guys do it, but it sounds like you do one of two things.
1) The user clicks a "I forgot my password" button and the new password is sent to the user.
2) The user clicks a "I forgot my password" button and then has to answer a security question before getting the new password emailed to the address on file.
Seems to me that option number 2 is more secure.
Why is sending a token any more secure than sending the password? If an email account has been hacked, it's been hacked. It doesn't matter if there is a link to reset the password, a token, or a new password. Don't forget, most sites don't say "The new password has been sent to the following email address for you to hack into". A hacker would need to guess the email address that needs to be hacked.
I agree with Andy. Aren't security questions normally independent of the password? (mine are) Meaning they have a question and an answer and aren't related to the password. It seems like this is used to prevent spurious password reset requests and actually does have a use.
Imagine - someone could go to a site's "forgot password" utility and enter a zillion email addresses - or just one person they want to annoy. If the password is reset at that point, the people belonging to those email addresses would have to then notice in their email the password reset and login to the site with the reset password next time they went there. With the security question, this isn't as easy for someone to do.
I see Amazon sends a link to the given email. They also require you to enter a captcha to prevent DOS attacks. Because it's a link, I imagine that means they did not reset the password immediately and it would be reset once the user clicks the link. With the scenario above, the user would just see the email and note that "no I didn't do that" and go about their business not having to change their password needlessly. A security question might have prevented the attempt at the beginning and the legit user from getting the email in the first place.
Here's a whitepaper on it:
http://appsecnotes.blogspot.com/2010/09/latest-forgot-password-best-practices.html
This one actually recommends secret questions as a major part of the authentication process. And sending an authentication code via email and requesting it is just an add-on layer you can optionally include.
It really comes down to how much security you want to have. One the one end of the extreme is a password reset process that involves contacting and certifying that you are who you claim to be, e.g. via id, because your mailbox could be compromised as well. Actually, as people tend to use the same password everywhere this is very likely. On the other end there is the standard approach that involves just sending out an email with a random new password.
"Secret" questions and answers are just another form of username and passwords with the fatal flaw that they are usually incredibly easy to guess, so good that you don't want to use them.
To your point about the token, I don't think it makes a big difference in overall security. Whether you send out a token that allows a user to change the password or whether you send out a random password right away doesn't make a big difference.
Just make sure the token is only usable once and preferably only in a limited time span, e.g. +24h after requesting it.
And, as pointed out by previous answers, NEVER EVER store plain passwords. Hash them. Preferably add salt.
Here's how I resolved it:
I added retrieve_token and retrieve_expiration fields to my 'users' table.
The user requests a password reset by providing their email and filling out captcha. A random hashed value is generated for their retrieve_token field - i.e. md5($user_id.time()), while retrieve_expiration will be set to a datetime that expires in next 45 minutes. Email is sent out to the user with a link:
https://example.com/reset-password?retrieve_token=912ec803b2ce49e4a541068d495ab570
SSL should be mandatory when authentication is required. You can also add a table for logging reset requests that stores email and the IP address. It helps track down possible brute attacks and you can block attacker's IP if necessary.
You could implement security question for requesting password reset, but I feel captcha would be enough to discourage anyone from repeating the request multiple times.
#Jay. The reason why you go to a URL to reset your password instead of just sending someone a new temporary password is more than just security. Without something like a URL with a token, a person could reset another persons password. There is no need to gain access to the email. If someone had a bone to pick with someone, they could just keep initiating a new password reset. Then the poor target has to logon and change the password again and again.
By sending a token, the user's password does not change until they login with it and confirm it. The spam of reset emails can be ignored. Tokens are just as easy (if not easier) to generate as a new password by using a GUID, it's not really extra hassle for the developer.
Also, because the GUID is unique (a generated password might not be), a token can be tied to a username. If the incorrect username is given on the URL, then the token can be cancelled (i.e. when a different person initiates it and someone intercepts it.. assuming that the username isn't the same as the email).
#Jay. The proper use of security questions is to initiate a password reset email, not for actually resetting the password. Without a mechanism such as a security question, one could initiate a password reset. Althought seemingly beign, sending a reset email could be sent to an email that might no longer belong to the original owner. This is not rare. For example, when employees leave a company, often those mails are forwarded to another employee. A security question, adds a low level of obfucation to that scenario. It also reduces issues where one person keeps initiating a password reset on the wrong account causing some poor sod to get unintentionally spammed. Security question are really not meant to be truely secure, they are just meant to reduce scenarios such as those. Anyone using a security question to actually reset the password is doing it wrong.
Regarding security question/answer. As a user of websites I personally don't use them (I enter garbage in them). But they are certainly not useless or meaningless as some say here.
Consider this situation:
A user of your site has left his desk to go to lunch and didn't lock his workstation. A nefarious user can now visit the page for recovering/resetting password and enter the user's username. The system will then email the recovered/reset password without prompting for the security answer.
Here's an example of how someone did it with Node.js, basically generate a random token, an expiry time, send out the link with the token attached, have a reset/:token route that ensures a user exists with that token (which is also not expired) and, if so, redirect to a reset password page.
http://sahatyalkabov.com/how-to-implement-password-reset-in-nodejs/

How to implement Querystring authentication

I’m developing a website of a client and they are sending out newsletters to their customers (through the website administration interface)
The newsletters are personal to each of the subscribed recipients/customers.
Each recipient/ customer is also a user with a username/password that enables them to sign in on the website and manage their newsletter subscriptions and participate in the sites community.
This all works like a charm.
Now my client want a “Manage my subscriptions” link in the newsletter email that when pressed automatically signs the recipient/customer in on the website with no need to remember username and password.
This could be easily solved be making a link like this:
http://mysite.com/manage.aspx?user=peter&password=hounddog
Of course information should not be clear text but encrypted in some way.
This however poses a problem since the only way a user can be authenticated on the website if by providing a valid username and password.
In the name of security, passwords are stored as hashed values in the database making it impossible for me to insert the password in the link.
What is the best way to accomplish this without compromising the security?
You will have to compromise your security somewhat, if you want people to be able to login without entering password. Note that even if you had access to the password (as in your example), you would have to embed it in a mail massage which would be transmitted in plaintext.
You can create a Guid associated with each user and message, and append it to the URL, and allow that to login automatically.
You could perhaps isolate the permissions so that a login through a newsletter guid link only allows the user to manage subscriptions, but that a real password-login is still required to participate in the forum. In that case its pretty limited what havoc can be wrecked if someone gets access to a Guid from a mail message.
Could you not insert an encrypted user name bundled with the hash value of the password?
What I mean is, encrypt & encode the user name to always be a particular length or to have a known break character in it then append the passwords hash value. this way, you could break apart the query string easily while still having the user name and password securely encoded. A straight compare of the hash values would be enough, with the unencrypted, decoded user name to allow access.
What about using an encrypted cookie that contains an access token ?
This cookie would be delivered after a successfull authentication by a separate page.
This kind of token can also be part of the URL query string.
Also you might consider using secured https instead of http.