cron enumeration

cat /etc/crontab ; ls -la /etc/cron.* ; crontab -l

Enumerates system and user scheduled tasks: /etc/crontab, cron.d/daily/hourly directories, and the current user's crontab. Each script executed by cron as root is a privilege escalation candidate if writable.

When you want the full inventory of periodic tasks on the host. The combination of the three commands covers almost everything: /etc/crontab for system tasks, /etc/cron.* for frequency-based directories, and crontab -l for the current user's tasks. Then check permissions on referenced scripts.

If you only care about your own crontab, the rest is unnecessary. On macOS, periodic task management is mostly launchd, so for modern macOS hosts complement with launchctl list: classic crontabs are barely used there.