I created compose-lint, a security linter for Docker Compose files, and pointed it at 6,444 public docker-compose.yml and compose.yaml files from GitHub. (More on why below.)

Three numbers stood out:

91% of the files that parse have at least one security finding.

68% have at least one HIGH or CRITICAL finding.

The same three issues top every category I looked at, including the official vendor examples people are told to copy.