vagrant/keys/README.md

Insecure Keypair

These keys are the "insecure" public/private keypair we offer to base box creators for use in their base boxes so that vagrant installations can automatically SSH into the boxes.

If you're working with a team or company or with a custom box and you want more secure SSH, you should create your own keypair and configure the private key in the Vagrantfile with config.ssh.private_key_path