I developed my Heroku app that exposes APIs only (no UI) and it works fine.
But how can I restrict the APIs to certain authorized/authenticated users only?
I absolutely need an authentication layer to protect the app APIs and prevent unauthorized accesses. A sort of login(user, psw) call to use before an external system can start invoking my API.
But I don't find any reference in the docs, it only says that these are the main security best practices:
Heroku SSL
Force the use of HTTPS
Trusted IP Range
Any idea?
That's something you'll need to implement at the application layer and not something that Heroku provides. At it's simplest you could implement basic auth in your app so that the user would pass them with their request, a more complex solution would involve user accounts and oauth etc etc.
You could implement all the authentication logic directly in your app.
Alternatively, take a look Auth0, which basically provides you with authentication and identity management as a service. You can easily add Auth0 to your Heroku app as a free add-on via the Heroku Elements marketplace.
They have lots of different use-cases and associated walk-throughs, and they offer a very generous free-tier.
From your requirements, it sounds like you might want to look at Auth0 Machine to Machine applications, using the OAuth2 Client Credentials Grant. With that, your external system(s) would basically need to authenticate with Auth0 using a Client Id and Client Secret (that you could generate in Auth0 and supply to them). Then, they would access your API with a JWT that you could easily validate in your app (Auth0 will provide you with generated code in many different languages for you to do that very easily). Your API will then reject requests without a valid JWT (by sending a "401 Unauthorized" response).
This may all sound a little intimidating at first, but it's really worth going through the relevant Auth0 "quickstart". They really go out of their way to try to make it as easy as possible!
Related
I have currently developed a backend app that has some important functionalities. I want to consume my backend endpoints from my frontend but I want to be sure that only my fronted calls the backend endpoint and no other. Currently anyone that access my web-app can take advantage of the functionalities (I do not require any user registration or authentication).
How can I be safe that my backend is not being called form other possible malicious attackers that may try to steal the functionalities of my backend?
I have read some other posts regarding solutions how to secure a backend app that do not require user authentication but none has a precise and secure way for that. Some say enabling CORS but during my experience I can say that CORS can be manipulated easily with the help of a simple browser plugin. (not speaking about mobile apps that do not consider it at all)
I would really appreciate if I would have some opinions in case of a web-frontend-app, mobile app and other backend systems that would try to call my API and how can I stop them.
Typical front-end authentication would be best (OpenID, ...).
If you want something different, you could check on your backend whether a specific header with a specific token is sent in the query. If it is not then you send back a 401 HTTP code.
This requires that your customers somehow get that token (through some registration process, probably) and then keep it long-term (it can be stored in LocalStorage but can be lost when cleaning up the browser)
OWASP Authentication is a good source of information.
I want to design a SPA which will have Frontend (React) and Backend-Rest API (Node.js, Express, Mongo DB). I am planning to have Single Sign-On in my application where users would be authenticating using MS-Azure AD, where a call would go to Azure AD from Frontend and in return I will get a token for that User which will be stored locally. After that, I want to call my rest API, for multiple GET, POST, PUT operations in the context of current user logged in on UI. Planning to deploy both frontend and backend on different servers so here I have two questions about securing my REST API.
CORS Implementation
User-Authentication on BE
Given the above requirements is it enough to have just CORS implemented or Do I need to again authenticate the User on BE?
Can somebody provide some best practice or experiences? Is there a lack in my “architecture”?
While CORS is definitely a consideration, it isn't Authentication (AuthN) or Authorization (AuthZ) which you need.
Depending on the number of users your application will have, how the back end will scale you might want to look at OAuth2.0 or stick with simpler session based auth but you will need something.
CORS on your back end will limit if a browser running an app on a domain other than yours to call your web services (it wont stop API requests from other tools).
AuthN - Your not logged in - go get logged in and come back to
me.
AuthZ - Controls what your users can and cant do. You might want to
enforce this at the resource level but you absolutely need to within
your business logic.
Further reading https://auth0.com/docs/authorization/concepts/authz-and-authn
Philippe from Pramgmatic web security has a free online course to get you started: https://pragmaticwebsecurity.com/courses/introduction-oauth-oidc.html Its very well paced and should give you some foundational knowledge. (It might let you write off OAuth for this use case but give it a go)
CORS will not perform any user authentication. You need CORS only when your client code is served from another domain than the backend you are talking too. If it is the same server to host static client files and backends REST endpoint, you don't need CORS. If you are unsure, then don't consider CORS at all and see if it works.
But you need authentication to know which user is which.
Thanks for your help in advance.
I'm using React Native and Node.js to deliver a product for my company.
I've setup the steps on the backend to retrieve a password, validate it and respond with a token. The only problem is - the password I use on the front end (mobile app) to be validated by the back end is hardcoded.
My question is:
How should I securely store this password on the mobile app so that it can not be sniffed out by a hacker and used to compromise the backend?
My research so far.
Embedded in strings.xml
Hidden in Source Code
Hidden in BuildConfigs
Using Proguard
Disguised/Encrypted Strings
Hidden in Native Libraries
http://rammic.github.io/2015/07/28/hiding-secrets-in-android-apps/
These methods are basically useless because hackers can easily circumnavigate these methods of protection.
https://github.com/oblador/react-native-keychain
Although this may obfuscate keys, these still have to be hardcoded. Making these kind of useless, unless I'm missing something.
I could use a .env file
https://github.com/luggit/react-native-config
Again, I feel like the hacker can still view secret keys, even if they are saved in a .env
I want to be able to store keys in the app so that I can validate the user an allow them to access resources on the backend. However, I don't know what the best plan of action is to ensure user/business security.
What suggestions do you have to protect the world (react- native apps) from pesky hackers, when they're stealing keys and using them inappropriately?
Your Question
I've setup the steps on the backend to retrieve a password, validate it and respond with a token. The only problem is - the password I use on the front end (mobile app) to be validated by the back end is hardcoded.
My question is:
How should I securely store this password on the mobile app so that it can not be sniffed out by a hacker and used to compromise the backend?
The cruel truth is... you can't!!!
It seems that you already have done some extensive research on the subject, and in my opinion you mentioned one effective way of shipping your App with an embedded secret:
Hidden in Native Libraries
But as you also say:
These methods are basically useless because hackers can easily circumnavigate these methods of protection.
Some are useless and others make reverse engineer the secret from the mobile app a lot harder. As I wrote here, the approach of using the native interfaces to hide the secret will require expertise to reverse engineer it, but then if is hard to reverse engineer the binary you can always resort to a man in the middle (MitM) attack to steel the secret, as I show here for retrieving a secret that is hidden in the mobile app binary with the use of the native interfaces, JNI/NDK.
To protect your mobile app from a MitM you can employ Certificate Pinning:
Pinning is the process of associating a host with their expected X509 certificate or public key. Once a certificate or public key is known or seen for a host, the certificate or public key is associated or 'pinned' to the host. If more than one certificate or public key is acceptable, then the program holds a pinset (taking from Jon Larimer and Kenny Root Google I/O talk). In this case, the advertised identity must match one of the elements in the pinset.
You can read this series of react native articles that show you how to apply certificate pinning to protect the communication channel between your mobile app and the API server.
If you don't know yet certificcate pinning can also be bypassed by using tools like Frida or xPosed.
Frida
Inject your own scripts into black box processes. Hook any function, spy on crypto APIs or trace private application code, no source code needed. Edit, hit save, and instantly see the results. All without compilation steps or program restarts.
xPosed
Xposed is a framework for modules that can change the behavior of the system and apps without touching any APKs. That's great because it means that modules can work for different versions and even ROMs without any changes (as long as the original code was not changed too much). It's also easy to undo.
So now you may be wondering how can I protect from certificate pinning bypass?
Well is not easy, but is possible, by using a mobile app attestation solution.
Before we go further on it, I would like to clarify first a common misconception among developers, regarding WHO and WHAT is accessing the API server.
The Difference Between WHO and WHAT is Accessing the API Server
To better understand the differences between the WHO and the WHAT are accessing an API server, let’s use this picture:
The Intended Communication Channel represents the mobile app being used as you expected, by a legit user without any malicious intentions, using an untampered version of the mobile app, and communicating directly with the API server without being man in the middle attacked.
The actual channel may represent several different scenarios, like a legit user with malicious intentions that may be using a repackaged version of the mobile app, a hacker using the genuine version of the mobile app, while man in the middle attacking it, to understand how the communication between the mobile app and the API server is being done in order to be able to automate attacks against your API. Many other scenarios are possible, but we will not enumerate each one here.
I hope that by now you may already have a clue why the WHO and the WHAT are not the same, but if not it will become clear in a moment.
The WHO is the user of the mobile app that we can authenticate, authorize and identify in several ways, like using OpenID Connect or OAUTH2 flows.
OAUTH
Generally, OAuth provides to clients a "secure delegated access" to server resources on behalf of a resource owner. It specifies a process for resource owners to authorize third-party access to their server resources without sharing their credentials. Designed specifically to work with Hypertext Transfer Protocol (HTTP), OAuth essentially allows access tokens to be issued to third-party clients by an authorization server, with the approval of the resource owner. The third party then uses the access token to access the protected resources hosted by the resource server.
OpenID Connect
OpenID Connect 1.0 is a simple identity layer on top of the OAuth 2.0 protocol. It allows Clients to verify the identity of the End-User based on the authentication performed by an Authorization Server, as well as to obtain basic profile information about the End-User in an interoperable and REST-like manner.
While user authentication may let the API server know WHO is using the API, it cannot guarantee that the requests have originated from WHAT you expect, the original version of the mobile app.
Now we need a way to identify WHAT is calling the API server, and here things become more tricky than most developers may think. The WHAT is the thing making the request to the API server. Is it really a genuine instance of the mobile app, or is a bot, an automated script or an attacker manually poking around with the API server, using a tool like Postman?
For your surprise you may end up discovering that It can be one of the legit users using a repackaged version of the mobile app or an automated script that is trying to gamify and take advantage of the service provided by the application.
Well, to identify the WHAT, developers tend to resort to an API key that usually they hard-code in the code of their mobile app. Some developers go the extra mile and compute the key at run-time in the mobile app, thus it becomes a runtime secret as opposed to the former approach when a static secret is embedded in the code.
The above write-up was extracted from an article I wrote, entitled WHY DOES YOUR MOBILE APP NEED AN API KEY?, and that you can read in full here, that is the first article in a series of articles about API keys.
Mobile App Attestation
The use of a Mobile App Attestation solution will enable the API server to know WHAT is sending the requests, thus allowing to respond only to requests from a genuine mobile app while rejecting all other requests from unsafe sources.
The role of a Mobile App Attestation service is to guarantee at run-time that your mobile app was not tampered, is not running in a rooted device and is not being the target of a MitM attack. This is done by running a SDK in the background that will communicate with a service running in the cloud to attest the integrity of the mobile app and device is running on. The cloud service also verifies that the TLS certificate provided to the mobile app on the handshake with the API server is indeed the same in use by the original and genuine API server for the mobile app, not one from a MitM attack.
On successful attestation of the mobile app integrity a short time lived JWT token is issued and signed with a secret that only the API server and the Mobile App Attestation service in the cloud are aware. In the case of failure on the mobile app attestation the JWT token is signed with a secret that the API server does not know.
Now the App must sent with every API call the JWT token in the headers of the request. This will allow the API server to only serve requests when it can verify the signature and expiration time in the JWT token and refuse them when it fails the verification.
Once the secret used by the Mobile App Attestation service is not known by the mobile app, is not possible to reverse engineer it at run-time even when the App is tampered, running in a rooted device or communicating over a connection that is being the target of a Man in the Middle Attack.
So this solution works in a positive detection model without false positives, thus not blocking legit users while keeping the bad guys at bays.
What suggestions do you have to protect the world (react- native apps) from pesky hackers, when they're stealing keys and using them inappropriately?
I think you should relaly go with a mobile app attestation solution, that you can roll in your own if you have the expertise for it, or you can use a solution that already exists as a SAAS solution at Approov(I work here), that provides SDKs for several platforms, including iOS, Android, React Native and others. The integration will also need a small check in the API server code to verify the JWT token issued by the cloud service. This check is necessary for the API server to be able to decide what requests to serve and what ones to deny.
Summary
I want to be able to store keys in the app so that I can validate the user an allow them to access resources on the backend. However, I don't know what the best plan of action is to ensure user/business security.
Don't go down this route of storing keys in the mobile app, because as you already know, by your extensive research, they can be bypassed.
Instead use a mobile attestation solution in conjunction with OAUTH2 or OpenID connect, that you can bind with the mobile app attestation token. An example of this token binding can be found in this article for the check of the custom payload claim in the endpoint /forms.
Going the Extra Mile
OWASP Mobile Security Project - Top 10 risks
The OWASP Mobile Security Project is a centralized resource intended to give developers and security teams the resources they need to build and maintain secure mobile applications. Through the project, our goal is to classify mobile security risks and provide developmental controls to reduce their impact or likelihood of exploitation.
I am used to develop web apps using the Meteor JavaScript framework, which handles authentication. I am now developing for the first time a web app using a Node.js (Express) + GraphQL stack on the backend, with React on the frontend, so I have to handle authentication myself.
I read a lot of things about it, and I like the idea of token based authentication. I am thinking about using JWT, so I don't have to deal with sessions.
I know there are a lot of tutorials, but each one always has a sort of disclaimer like : "this tutorial is not production ready, use it for educational purposes only...". Every time I read something about authentication, it seems to be something so difficult to implement that I shouldn't implement it myself. But I don't want to use services providers like AWS Cognito, Google Cloud Platform because I want to keep my users data in my own system and database. I don't want to be tied to a third party provider.
I know how to generate jwt tokens, refresh tokens, how to verify them, etc... I am able to develop a working auth system, but I am never sure I do it in a secure and production ready way because of all those comments I can read on the Internet.
So, what would you recommend to implement a secured and production ready authentication system in a Node.js server without being tied to a third-party provider. Do you know any complete tutorial or documentation about it?
There are several approaches to implement authentication for an application.
Use a identity server manage by you
Use a fully manage service for authentication.
Use authentication middleware.
Write your own authentication solution.
If you are afraid in vender locking I would suggest to use an authentication middleware like PassportJS which will facilitate the abstraction of authentication strategy with its implementation.
On the otherhand writing your custom authentication can be challenging in terms of security, specially finding snd fixing these vulnerabilities.
I have in the past done a hand rolled app that stores a user token on client side $window.sessionStorage.
I have since then realized this is not safe. I am now looking for the most safe, standard way to secure an app that uses a node/express backend api that I will make, and also uses a front end that makes requests to this api such as angular for web or a native mobile app. Plus, whenever I would close the browser, I would have to re-log in because the $window's session storage was wiped out.
From what I've researched thus far, one of the safest ways to date if you're going to handroll it is to store a jwt in an http only secure cookie.
However, I'd kind of like to use a service that already exists, such as oAuth. Couple questions:
1) How safe is oAuth in terms of keeping ownershp of your userbase? What if 3 years from now oAuth just suddenly or slowly dies out? Aren't all my users technically stored on their server? How would I keep my users native to my app?
2) If I'm going to be creating a startup app in the same realm as snapchat, twitter, tumblr, etc... would it be generally recommended to use a service like oAuth to handle my authentication? Of course the future is unknown, but assuming the best, that my app would reach millions of users, would using a service like oAuth still be a smart choice? It seems like once you start using oAuth, there's never any going back to storing your users in your own database a year or two down the road.
Thanks
OAuth is an open standard for authorization.
Maybe you're thinking about Auth0. There are a lot of services that can handle user authorization for you, including Auth0, Stormpath, Apigee, UserApp, AuthRocket or Amazon Cognito. Whichever you choose, make sure that you can get the database from them in case you want to stop using their service. Not everyone explicitly offers an easy way to leave them but if that's important for you then make sure who suits your needs and who doesn't, and base your decision on that.
As for OAuth, see the https://en.wikipedia.org/wiki/OAuth article.
There's a huge list of OAuth providers on Wikipedia but those are services like Twitter, Google or Facebook. In a way you can use one of those services to manage all your logins but as soon as they see you as their competition, you're in trouble. I've heard stories like that.
Some interesting read on the subject:
The dangers of OAuth/Social Login
Signing Me onto Your Accounts through Facebook and Google: a Traffic-Guided Security Study of Commercially Deployed Single-Sign-On Web Services
OpenID Vulnerability report: Data confusion
Social Login Setups – The Good, the Bad and the Ugly