IT Solutions Technology Blog

Trend Micro – SECURITY BULLETIN June 2025

Certificate Authority

Generate the Certificate Authority (CA) Private Key

Every certificate must have a corresponding private key. Generate this using the following command line

# openssl ecparam -name prime256v1 -genkey -noout -out ca.key

This will create a 256-bit private key over an elliptic curve, which is the industry standard. We know that Curve25519 is considered safer than this NIST P-256 curve but it is only standardized in TLS 1.3 which is not yet widely supported

Generate the Certificate Authority Certificate

The CA generates and issues certificates. Here is a link to additional resources if you wish to learn more about this.

Generate the Root CA certificate using the following command line

# openssl req -new -x509 -sha256 -key ca.key -out ca.crt

You will be prompted to provide some information about the CA. Here is what the request looks like:

You are about to be asked to enter information that will be incorporated into your certificate request
What you are about to enter is what is called a Distinguished Name or a DN

Country Name (2 letter code) [AU]:CA
State or Province Name (full name) [Some-State]:QC
Locality Name (eg, city) []:Lavaltrie
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Devolutions inc.
Organizational Unit Name (eg, section) []:Security
Common Name (e.g. server FQDN or YOUR name) []:devolutions.net
Email Address []:security@devolutions.net

Your CA certificate is now created. Keep its private key in a safe place

Generate your server certificate

This step may be repeated for each server you need

Generate the server certificate private key

Like the CA certificate use the following command line

# openssl ecparam -name prime256v1 -genkey -noout -out server.key

This will create a file name server.key