I recently had problems with the chaining with Stripe and Samsung Smartphones.
SSLLabs, https://tools.keycdn.com/ssl and Stripe say that I have chain issues. But they should not appear.
I use this in the following Certificate Chain:
LE X3 signed-by IdenTrust https://letsencrypt.org/certs/lets-encrypt-x3-cross-signed.pem.txt
LE X3 signed-by ISRG Root X1 https://letsencrypt.org/certs/letsencryptauthorityx3.pem.txt
But if I use the cert and the intermediate signed by ISRG Root X1 I get the message from keycdn.com that the chain is invalid.
Intermediate certificate required. Unable to get issuer certificate. 1. Subject CN: tobiassachs.de Issuer CN: Let's Encrypt Authority X3 2. Subject CN: Let's Encrypt Authority X3 Issuer CN: ISRG Root X1
Any Ideas what’s going on here because both are the only intermediates mentioned here https://letsencrypt.org/certificates/