SSH keys use strong encryption

How to fix

To check the strength of a key:

• Open Terminal app and type
  ssh-keygen -l -f ~/.ssh/id_rsa
• Replace id_rsa with the name of the key that was reported
• Press enter, the first returned value is key size

To check the strength of a key that you use in GitHub or GitLab:

• visit aremykeyssafe.com,
• enter the username/handle you use on the service to see the report.

Recommended key sizes are as follows:

• For the RSA algorithm at least 2048, recommended 4096
• The DSA algorithm should not be used
• For the ECDSA algorithm it should be 521
• For the ED25519 the key size should be 256 or larger

Sources NIST, SSH Academy.

If you want to create a new strong SSH key, the GitHub docs provide a great starting point.