Shohanur Rahman's blog

Authentication Evolution

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Shohanur Rahman
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3 min read

Agenda:

  • Overview of authentication mechanisms

  • Evolution from Username/Password to OAuth2

  • Security improvements and challenges

  • Next steps for improving authentication practices

1. Overview of Authentication

Authentication is the process of verifying the identity of users or systems before allowing access to resources. Over the years, this has evolved from simple methods (username/password) to more complex and secure standards (OAuth2).

2. Authentication Evolution

A. Username & Password Authentication (Traditional Method)

  • What is it?

    • The simplest and oldest form of authentication. A user enters a username and password, which are sent to the server for validation.

  • Issues:

    • Weak Security: Passwords are often weak or reused across multiple platforms, increasing the risk of breaches.

    • Insecure Storage: If passwords are not securely stored (e.g., hashed and salted), attackers can easily steal them from databases.

    • Phishing Attacks: Users are vulnerable to phishing schemes where credentials can be stolen.

B. Basic Authentication

  • What is it?

    • A simple authentication scheme built into HTTP, where a client sends the username and password in an encoded format (Base64) in the request header (Authorization: Basic <Base64-encoded-credentials>).

  • Pros:

    • Easy to implement for quick authentication.

  • Cons:

    • Insecure Transmission: Credentials are Base64-encoded but not encrypted, so if HTTPS is not used, they can easily be intercepted.

    • No Tokenization: Requires sending the credentials on every request, increasing exposure.

C. OAuth0

  • What is it?

    • OAuth0 is an identity provider (like Google, Facebook, etc.) that offers authentication and authorization services. It’s not a standard but rather a specific implementation of OAuth.

  • Use Case:

    • Third-party applications can use OAuth0 to authenticate users without directly handling their credentials. OAuth0 allows users to log in with social platforms (Google, Facebook, etc.).

  • Pros:

    • Offloads the responsibility of managing passwords to a third party.

    • Provides social login functionality.

  • Cons:

    • Relies on the identity provider (OAuth0), which might lead to vendor lock-in.

D. OAuth2 (Modern Standard)

  • What is it?

    • OAuth2 is the modern and most widely used authorization framework. It allows third-party services to exchange tokens on behalf of the user without exposing credentials. OAuth2 focuses on delegation, not direct authentication like username/password or Basic Auth.

  • How it works:

    • OAuth2 introduces the Authorization Code Flow:

      1. Client Requests Authorization: A client (e.g., a mobile app) requests permission from the user to access resources on another service.

      2. User Grants Authorization: The user is redirected to the authorization server to log in (often via a service like Google).

      3. Authorization Server Issues a Code: If the user approves, the authorization server provides an authorization code to the client.

      4. Exchange Code for Access Token: The client exchanges this code for an access token, which it uses to request resources on behalf of the user.

  • Pros:

    • Improved Security: Tokens are used instead of credentials, reducing the risk of exposing passwords.

    • Fine-grained Authorization: Permissions can be scoped to specific resources or actions.

    • Token Revocation: Access tokens can be easily revoked without affecting user credentials.

  • Challenges:

    • Token Security: Access tokens need to be secured, as they grant access to resources. If compromised, they can be abused.

    • Complexity: OAuth2 introduces more complexity compared to traditional username/password methods.

3. Security Improvements

  • Encryption: Ensure all communication (e.g., OAuth2) happens over HTTPS to prevent token interception.

  • Token Expiration and Revocation: Implement short-lived access tokens with refresh tokens to minimize the impact of token theft.

  • Multi-factor Authentication (MFA): Enhance security by requiring additional authentication factors beyond username and password.

4. Next Steps

  • Evaluate the current authentication implementation and identify potential risks.

  • Consider migrating to OAuth2 for modern and secure authorization mechanisms.

  • Implement best practices for token security (e.g., token expiration, revocation).

  • Explore additional identity providers (like OAuth0) for handling authentication without password storage