App using Cognito for SSO? Use this Methodology to find High Severity Issues

Photo by Ed Hardie on Unsplash

Hi everyone. With AI on the rise, I’ve seen a lot of vibe coded applications and applications built solely by AI agents (with no Human intervention), relying on authentication solutions such as AWS Cognito.

What is AWS Congito?

Amazon Cognito is a fully managed AWS service providing secure identity management, authentication, and authorization for web and mobile apps.

There are two main concepts that we need to understand in Cognito:

• User Pools
• Identity Pools

User Pools: It acts as a user directory for sign-up/sign-in. All the users who have an account on the application or who have registered are reflected on the User Pools in AWS Congito. These handle:

• User registration (signup)
• Authentication (login)
• JWT token issuance (after successful login)

Identity Pools: Let’s say the application requires users to access certain AWS services such as S3 buckets, etc., then the application can request AWS temporary credentials on behalf of the user and store them on the browser. This handles:

• Exchange JWT tokens (that we got from User Pools after…