How do I troubleshoot the "InvalidIdentityToken" error when I use the Amazon EKS IAM role to access the service account?

Resolution

Amazon EKS service accounts use OpenID Connect (OIDC) to authenticate. When you create an AWS Identity and Access Management (IAM) OIDC identity provider (IdP) for your Amazon EKS cluster, the thumbprint that's generated uses the root certificate. The Amazon root Certificate Authority (CA) has a validation period of approximately 25 years.

You receive the "WebIdentityErr: failed to retrieve credentials\r\ncaused by: InvalidIdentityToken: OpenIDConnect provider's HTTPS certificate doesn't match configured thumbprint\r\n" error in the following scenarios:

• The thumbprint that's used in the OIDC provider is expired.
• The thumbprint doesn't match the CA.

To troubleshoot this issue and obtain a thumbprint, install and configure the OpenSSL command line tool.

Find the URL for the OIDC IdP

To find the URL for the OIDC IdP, complete the following steps:

1. Open the Amazon EKS console.

2. In the navigation pane, choose Clusters.

3. Select the cluster that you want to check.

4. Choose the Configuration tab.

5. Under the Details section, note the OIDC IdP URL.
   Example: https://oidc.eks.us-east-1.amazonaws.com/id/1111222233334444555566667777888F/

   Include /.well-known/openid-configuration at the end of the OIDC IdP URL to form the URL for the IdP's configuration document.

   Example: https://oidc.eks.us-east-1.amazonaws.com/id/1111222233334444555566667777888F/.well-known/openid-configuration. Access this URL in a web browser, and note the jwks_uri value from the output. The browser output looks similar to the following:

   {"issuer":"https://oidc.eks.us-east-1.amazonaws.com/id/1111222233334444555566667777888F","jwks_uri":"https://oidc.eks.us-east-1.amazonaws.com/id/1111222233334444555566667777888F/keys","authorization_endpoint":"urn:kubernetes:programmatic_authorization","response_types_supported":["id_token"],"subject_types_supported":["public"],"claims_supported":["sub","iss"],"id_token_signing_alg_values_supported":["RS256"]}

Display certificates

Use the OpenSSL command line tool to run the following command to display all the certificates that are used:
Note: Replace oidc.eks.us-east-2.amazonaws.com with your domain name.

openssl s_client -connect oidc.eks.us-east-2.amazonaws.com:443 -showcerts

The output looks similar to the following:

[root@ip-172-31-1-202 ~]# openssl s_client -connect oidc.eks.us-east-2.amazonaws.com:443 -showcertsCONNECTED(00000003)
depth=4 C = US, O = "Starfield Technologies, Inc.", OU = Starfield Class 2 Certification Authority
verify return:1
depth=3 C = US, ST = Arizona, L = Scottsdale, O = "Starfield Technologies, Inc.", CN = Starfield Services Root Certificate Authority - G2
verify return:1
depth=2 C = US, O = Amazon, CN = Amazon Root CA 1
verify return:1
depth=1 C = US, O = Amazon, OU = Server CA 1B, CN = Amazon
verify return:1
depth=0 CN = *.execute-api.us-east-2.amazonaws.com
verify return:1
---
Certificate chain
 0 s:/CN=*.execute-api.us-east-2.amazonaws.com
   i:/C=US/O=Amazon/OU=Server CA 1B/CN=Amazon
-----BEGIN CERTIFICATE-----
CERTIFICATE Redacted
-----END CERTIFICATE-----
 1 s:/C=US/O=Amazon/OU=Server CA 1B/CN=Amazon
   i:/C=US/O=Amazon/CN=Amazon Root CA 1
-----BEGIN CERTIFICATE-----
CERTIFICATE Redacted
-----END CERTIFICATE-----
 2 s:/C=US/O=Amazon/CN=Amazon Root CA 1
   i:/C=US/ST=Arizona/L=Scottsdale/O=Starfield Technologies, Inc./CN=Starfield Services Root Certificate Authority - G2
-----BEGIN CERTIFICATE-----
CERTIFICATE Redacted
-----END CERTIFICATE-----
 3 s:/C=US/ST=Arizona/L=Scottsdale/O=Starfield Technologies, Inc./CN=Starfield Services Root Certificate Authority - G2
   i:/C=US/O=Starfield Technologies, Inc./OU=Starfield Class 2 Certification Authority
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
---
Server certificate
subject=/CN=*.execute-api.us-east-2.amazonaws.com
issuer=/C=US/O=Amazon/OU=Server CA 1B/CN=Amazon

If you see more than one certificate in the output, then look for the last certificate at the end of the output. The last certificate is the root CA in the certificate authority chain.

Create a certificate file

Create a certificate file (example: certificate.crt), and copy the contents of the last certificate to the file.

Then, run the following command:

openssl x509 -in certificate.crt -text

The output looks similar to the following:

[root@ip-172-31-1-202 ~]# openssl x509 -in certificate.crt -textCertificate:    Data:
        Version: 3 (0x2)
        Serial Number:
            a7:0e:4a:4c:34:82:b7:7f
    Signature Algorithm: sha256WithRSAEncryption
        Issuer: C=US, O=Starfield Technologies, Inc., OU=Starfield Class 2 Certification Authority
        Validity
            Not Before: Sep  2 00:00:00 2009 GMT
            Not After : Jun 28 17:39:16 2034 GMT

Check the validity of the certificate from the values in the Not Before and Not After fields. In the preceding output, the validity of the CA is approximately 25 years.

Replace an expired certificate

If the output shows that the certificate is expired, then you must renew the certificate with your OIDC IdP.

After you renew the certificate, run the following command with the OpenSSL command line tool to get the latest thumbprint:

openssl x509 -in certificate.crt -fingerprint -noout

The output looks similar to the following:

SHA1 Fingerprint=9E:99:A4:8A:99:60:B1:49:26:BB:7F:3B:02:E2:2D:A2:B0:AB:72:80

Delete the colons (:) from this string to get the final thumbprint:

9E99A48A9960B14926BB7F3B02E22DA2B0AB7280

Run the following command to get the latest thumbprint:

$ openssl x509 -in certificate.crt -fingerprint -noout | sed s/://g

Update to the latest thumbprint 

If the current thumbprint is expired, then use the IAM console or AWS Command Line Interface (AWS CLI) to replace it with the latest thumbprint.

IAM console

To use the IAM console, complete the following steps:

1. Open the IAM console.
2. In the navigation pane, choose Identity providers.
3. Choose the IdP that you want to update.
4. In the Thumbprints section, choose Manage.
5. Choose Add thumbprint, and then enter the new value.
6. Choose Save changes.

AWS CLI

Note: If you receive errors when you run AWS Command Line Interface (AWS CLI) commands, then see Troubleshoot AWS CLI errors. Also, make sure that you're using the most recent AWS CLI version.

Run the update-open-id-connect-provider-thumbprint AWS CLI command:

aws iam update-open-id-connect-provider-thumbprint --open-id-connect-provider-arn arn:aws:iam::111122223333:oidc-provider/oidc.eks.us-east-1.amazonaws.com/id/5ECB2797CB1324A37FC79E3C46851CED --thumbprint-list 9E99A48A9960B14926BB7F3B02E22DA2B0AB7280

Related information

Creating OpenID Connect (OIDC) identity providers