Permissions 0755 for 'certificate.pem' are too open

You may experience bad permission error and ignoring operation while running a command with AWS.

It's because a AWS are concern about your security and make sure the certificate are only accessible by you, not even to read them or discover their names. That's basic sensible security and it means no permissions whatsoever for group or world.

You should own the directory and the permission should be something like 600 or 400 or 700.

To fix the issue change permission like:

chmod 400 certificate.pem