Using the ID token - Amazon Cognito

Using the ID token

The ID token is a JSON web token (JWT) that contains claims about the identity of the authenticated user, such as name, email, and phone_number. You can use this identity information inside your application. The ID token can also be used to authenticate users to your resource servers or server applications. You can also use an ID token outside of the application with your web API operations. In those cases, you must verify the signature of the ID token before you can trust any claims inside the ID token. See Verifying a JSON web token.

You can set the ID token expiration to any value between 5 minutes and 1 day. You can set this value per app client.

Important

When your user signs in with the hosted UI or a federated identity provider (IdP), Amazon Cognito sets session cookies that are valid for 1 hour. If you use the hosted UI or federation, and specify a minimum duration of less than 1 hour for your access and ID tokens, your users will still have a valid session until the cookie expires. If the user has tokens that expire during the one-hour session, the user can refresh their tokens without the need to reauthenticate.

ID Token Header

The header contains two pieces of information: the key ID (kid), and the algorithm (alg).

{
"kid" : "1234example=",
"alg" : "RS256"
}
kid

The key ID. Its value indicates the key that was used to secure the JSON Web Signature (JWS) of the token. You can view your user pool signing key IDs at the jwks_uri endpoint.

For more information about the kid parameter, see the Key identifier (kid) header parameter.

alg

The cryptographic algorithm that Amazon Cognito used to secure the access token. User pools use an RS256 cryptographic algorithm, which is an RSA signature with SHA-256.

For more information about the alg parameter, see Algorithm (alg) header parameter.

ID Token Payload

This is a sample payload from an ID token. It contains claims about the authenticated user. For more information about OpenID Connect (OIDC) standard claims, see the OIDC standard claims.

<header>.
{
   "sub":"aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee",
   "cognito:groups":[
      "my-test-group"
   ],
   "email_verified":true,
   "cognito:preferred_role":"arn:aws:iam::111122223333:role/my-test-role",
   "iss":"https://cognito-idp.us-west-2.amazonaws.com/us-west-2_example",
   "cognito:username":"my-test-user",
   "middle_name":"Jane",
   "nonce":"abcdefg",
   "origin_jti":"aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee",
   "cognito:roles":[
      "arn:aws:iam::111122223333:role/my-test-role"
   ],
   "aud":"xxxxxxxxxxxxexample",
   "event_id":"64f513be-32db-42b0-b78e-b02127b4f463",
   "token_use":"id",
   "auth_time":1676312777,
   "exp":1676316377,
   "iat":1676312777,
   "jti":"aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee",
   "email":"my-test-user@example.com"
}
.<token signature>
sub

A unique identifier (UUID), or subject, for the authenticated user. The user name might not be unique in your user pool. The sub claim is the best way to identify a given user.

cognito:groups

An array of the names of user pool groups that have your user as a member.

cognito:preferred_role

The ARN of the IAM role that you associated with your user's highest-priority user pool group.

iss

The identity provider that issued the token. The claim has the following format.

https://cognito-idp.<Region>.amazonaws.com/<your user pool ID>

cognito:username

The user name of your user in your user pool.

nonce

The nonce claim comes from a parameter of the same name that you can add to requests to your OAuth 2.0 authorize endpoint. When you add the parameter, the nonce claim is included in the ID token that Amazon Cognito issues, and you can use it to guard against replay attacks. If you do not provide a nonce value in your request, Amazon Cognito automatically generates and validates a nonce when you authenticate through a third-party identity provider, then adds it as a nonce claim to the ID token. The implementation of the nonce claim in Amazon Cognito is based on OIDC standards.

origin_jti

A token-revocation identifier associated with your user's refresh token. Amazon Cognito references the origin_jti claim when it checks if you revoked your user's token with the Revoke endpoint or the RevokeToken API operation. When you revoke a token, Amazon Cognito invalidates all access and ID tokens with the same origin_jti value.

cognito:roles

An array of the names of the IAM roles associated with your user's groups.

aud

The user pool app client that authenticated your user. Amazon Cognito renders the same value in the access token client_id claim.

token_use

The intended purpose of the token. In an ID token, its value is id.

auth_time

The authentication time, in Unix time format, that your user completed authentication.

exp

The expiration time, in Unix time format, that your user's token expires.

iat

The issued-at time, in Unix time format, that Amazon Cognito issued your user's token.

jti

The unique identifier of the JWT.

The ID token can contain OIDC standard claims that are defined in OIDC standard claims. The ID token can also contain custom attributes that you define in your user pool. Amazon Cognito writes custom attribute values to the ID token as strings regardless of attribute type.

Note

User pool custom attributes are always prefixed with a custom: prefix.

ID Token Signature

The signature of the ID token is calculated based on the header and payload of the JWT token. Before you accept the claims in any ID token that your app receives, verify the signature of the token. For more information, see Verifying a JSON Web Token. Verifying a JSON web token.