Answer by milfar dean for Resolving javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed Error?

I ran into this issue while making REST calls from my app server running in AWS EC2. The following Steps fixed the issue for me.

1. curl -vs https://your_rest_path
2. echo | openssl s_client -connect your_domain:443
3. sudo apt-get install ca-certificates

curl -vs https://your_rest_path will now work!