Best way to safe pass username to other site - security

I have 1 legacy site and the other new.
The new site will be embedded into legacy site as an iframe.
In the new site I know the list of users registered in legacy site.
I want to know which user is opening my page, registered and logged in the legacy site.
What is the best way to pass username to new site from old site in HTTP URL with knowing that it is safe?
I was thinking about passing as GET parameter encrypted data, which will be decrypted in new site.
This data would contain username and timestamp and salt. In new site I will check if username is in my list of registered users, and I will grant acces for a particular time. Is that a secure way?
There is only HTTP without SSL.

You should use POST whenever you transmit secure data over HTTP , not because it provides any additional security over GET , but will avoid logging the sensitive info in Browser history and server logs.
Also instead of sending the encrypted credentials over HTTP you could generate some kind of Token out of it and pass it across which can be verified at the receiver end.

It looks pretty safe to me. You are delegating authentication to your new site and just signaling the old one. That should be safe provided your encryption method is.
Using salt and timestamp will take care of replay attacks, so I don't see any vulnerabilities in the method you propose, if you choose a safe encryption method, that is.

Sticking user info in the URL of a GET request may be safe if encrypted, it will ruin your caching as now the same page has a different URL for different users.
The thing that doesn't sound safe to me is that if both sites are served over HTTP, then the user could not have logged in safely to the old site. All traffic is in the clear and susceptible to eavesdropping.
I would recommend moving your site to HTTPS for both sites. If the sites are hosted on the same domain, you can set a cookie identifying the user that will work for both sites.
Even better would be to move to some social authentication provider like Facebook or Microsoft Live Id and avoid storing user passwords all together.

Related

Securing a https connection

I have exposed some rest services in spring, using spring mvc, I have secured the webapp using spring security, that uses bcrypt on the server to encode the password and store it in the datbase.
The user will send the password in the url in plain text under https, And i have written a custom basic_auth_filter to check the uername and passowrd - basically authenticate. I also have set up a firewall that only allows one ip to connect.
Im no security expert, is there anything else i need to, should i encode the username/password in the url.. even though it will be coming via https?
regards
ps. this was a requirement to use username on the url?
Passwords, and all other non-ephemeral credentials, should never be sent in the URL, if for no other reason then because the browsers and other HTTP tools and servers will remember this in history, various logs etc, HTTPS or not, making it trivial to steal by anyone with local access, or even by someone just looking over your shoulder. This is why Spring by default rejects authentication via GET requests.
For this reason, you should move the sensitive parameters to the body of the request (thus requiring a POST).
If your login flow is based on username/passwords, I recommend you use UsernamePasswordAuthenticationFilter as it already encapsulates the logic and best practices for this type of flow.
In general your scheme is secure.
Consider pinning the server, that is validating the server certificate, to ensure the connection is to your server.
The password should not be used other than to authenticate using (in your case) bcrypt.
Re question update: "HTTPS encrypts the query string, only the actual server address portion is un-encrypted. But, the full URL including query string will probably be logged by the server so that has security implication. It is best to send confidential information in a POST.

Does https make this any more secure?

I'm reading the API for a web service, and all methods involve sending an HTTP request to
https://example.com/api/APIVER/METHOD?apikey=APIKEY&user=USERNAME&password=PASSWORD
To be clear, both the API key and user password are sent in plain text via the URL. But is this OK because "all HTTPS traffic is encrypted" or not because they're still in plain text or because the URL is somehow different?
If this isn't secure, what is the minimum change the API maintainer needs to do?
Yes, HTTPS makes this more secure.
HTTPS makes this more secure.
You should also send sensitive parameters as POST parameters instead (HTTP BODY) of GET query string ones. Typically the query string will be logged by Web server logs (server side) in plaintext, so it will be accessible to system administrators that perhaps shouldn't be able to see it.
HTTPS will encode the URL in each request, so if you are worried about network sniffing then you're OK. HTTPS also adds a nonce value, so you aren't exposed to reply attacks.
It would be possible, depending on infrastructure to insert a fake SSL certificate that's trusted by the user device and route requests through a proxy using that certificate. However this would require admin/root access to the client machines to make such a certificate trusted (barring breach of a normally trusted CA), and once something needs admin access all bets are off anyway.
It's still not a wonderful idea though, I'd be concerned about developers forgetting to configure it for HTTPS. You have an API key, so why not take the password and hash it using the APIKEY as the salt. Now for the API calls the salt is a password equivalent but it would mean that the username and password couldn't be used for logging into elsewhere with those credentials, for example the web site that the API is running off (assuming you let users log in there of course.)
Even better would be to use a shared secret that doesn't go over the wire at all, and use that as the salt.

Security practices for internal web application

I am a developer working on an internal web-based application, and I have been given responsibility to make sure the system is secure. I have no experience in this area, but I still want to do the best job I can: I'm in the middle of reading OWASP's guide (http://surfnet.dl.sourceforge.net/project/owasp/Guide/2.0.1/OWASPGuide2.0.1.pdf), but there is a lot of information to process, and unfortunately deadlines are deadlines.
Can the knowledgeable users here at Stack Overflow please poke holes in my design and show me where my understanding is lacking? If the entire idea is fundamentally flawed, knowing that would be appreciated, too. Thanks for any input.
This application is hosted internally, and should not be visible at all externally, even though it is accessed over our wireless networks. I trust our network engineers to handle this, though.
The users of this application are only a subset of all the employees in this corporate environment. In addition, even authorized users should be limited to only the information pertaining to them (which is largely an application-level concern, but I want to make sure exploits are not possible).
Security Framework for Internal Web Application (by a newbie)
All communication with the web server is done over HTTPS connections.
Logging in
User enters name and password, which are POSTed over an HTTPS connection
If the name and password are correct, generate a token, and store it in a cookie. Also store the cookie in the database for future lookup. The token should have an expiration date and is associated with only the user that generated it.
Requests
Check that the token supplied is still valid (not expired)
Check that the token is valid for the user making the request
If everything checks out, refresh the token's validity for another 30 minutes (or so)
Otherwise, deny access
That sounds good.
The token can either be a signed expiration date (signed with a private key stored on the server) or a sequence of cryptographically secure random bytes which is stored in a database.
Unless the token is specific to an IP address, everything must be done over SSL.
Independently of authentication, you'll also need to look out for SQL injection, CSRF, XSS, and other security holes.
Important consideration: The entire session has to be over SSL. Firesheep has demonstrated quite clearly that being able to sniff cookies (by being on the same network as the victim) leaves your users open to session hijacking.
Security is more than just logging in. You'll want to read up on SQL Injection and Cross-Site Scripting Attacks, on the very least (the two most common attacks against web-applications).
Look into CSRF attacks. They bypass cookie checks and company firewalls.

OpenID authentication on AppEngine and non-AppEngine subdomains

I have a main website running on AppEngine. It's on a subdomain like main.example.com. This main application is a content portal for our customers. It offers an Ajax application built on YUI. Customers can upload data to it. Users authenticate using Federated Login.
The Ajax application on it allows users to process the data previously uploaded. To do it it should use an webservice running on other subdomain like service.example.com. The webservice does not run on AppEngine but on our services - it's CPU heavy and built on other set of technologies. It would need to download the data on main application - but the downloading service - like everything on the main application - is behind the authentication wall.
I could programatically always allow the service to download wharever it wishes but I think this can turn into a major security problem.
How can I reuse the OpenID authentication "token" to allow it (the service) to appears to the main application as the authenticated user so it can download data? Or If I can do this what would be the best way to accomplish what I intend to do?
You can't really reuse the authentication token. What you should use is something akin to OAuth, though since you control both ends you can make it somewhat simpler:
Generate a shared secret, accessible by both main.example.com and service.example.com
When a user accesses service.example.com for the first time (no authentication cookie), redirect them to main.example.com/auth?continue=original_url (where original_url is the URL they attempted to access)
When you receive a request to main.example.com/auth, first log the user in the regular way (if they're not already). Then, take their user ID or other relevant credentials, and generate an HMAC from them, using the shared secret you established in step 1. Redirect the user to service.example.com/finish_auth, passing the computed HMAC, the authentication details such as user ID, and any parameters you were passed in such as the continue URL.
When you receive a request to service.example.com/finish_auth, compute the HMAC as above, and check it matches the passed in one. If it does, you know the request is a legitimate one. Set an authentication cookie on service.example.com containing any relevant details, and redirect the user back to their original URL.
This sounds complicated, but it's fairly straightforward in implementation. This is a standard way to 'pass' credentials between mutually trusting systems, and it's not unlike what a lot of SSO systems use.

How to open a link from one web app to another already authenticated?

We have one web application (sharepoint) that collects information from disparate sources. We would like to be able to link users to the main websites of those various sources and have them pre-authenticated. I.E. they enter their credentials for the other sources (which are a number of different types LDAP, AD and home grown!) and we retrieve some information for them, and remember there details (Possibly Single Sign-on to keep em nice and safe). The user can then click a link that will open the full app in another window already authenticated.
Is this even likely to be possible?
Office Server has a Single-Sign-On api as a builtin feature. you may want to look into that. It enables you to register user credentials securely, and to access it at runtime.
You need to act as a web browser acts to different sites with storing credentials (usually in cookies) locally. Use therefore a a proper client library with cookie support. This could go probably for most of sites. There are sites using HTTP authentication, which are also easier to access from appropriate client libraries. The most demanding can be access to SSL websites, but again, most client HTTP libraries cover that nowadays as well.
All you need now is just to prepare your web application to act as a proxy to all those separate web resources. How exactly this is done in Sharepoint, well, I hope others will answer that...
True Single Sign-on is a big task. Wikipedia describes common methods and links to a few SSO projects.
If you want something lighter, I've used this approach in the past:
Create a table to store temporary security tokens somewhere that all apps can access.
From the source app (Sharepoint in your case), on request of an external app, save a security token (maybe a guid, tight expiration, and userid) in the token table.
Redirect to a request broker page/handler in the destination app. Include the final page requested and the guid in the request.
In the broker, look up the security token. If it exists and hasn't expired, authenticate, authorize, and redirect to the final page if everything is good. If not, send a permissions err.
Security-wise, a guid should be near impossible to guess. You can shrink risk by letting the tokens expire very quickly - it shouldn't take more than a few seconds to call the broker.
If the destination app uses Windows Auth and doesn't have role-based logic, you shouldn't have to do much. Just redirect and let your File/UrlAuthorization handle it. You can handle role-based permissions with the security token db if required.

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