An easy Linux box from HackTheBox, use a chain of two CVEs on Magento to get initial access, then abuse sudo privileges on vi to get root.

An easy box from HackTheBox, entirely AD - first get a user hash by AS-REP roasting and crack it for initial access with evil-winrm, then scrape AD information and use bloodhound to find a path to domain admin via group misconfigurations.

An easy Linux box from HackTheBox, get run around rabbit holes until finally discover a subdomain with a LFI, grab a SSH key and use that for initial access, then exploit a vulnerable configuration of fail2ban for root.

An easy Windows box from HackTheBox, leak admin creds to a voting dashboard via SSRF and upload a webshell for initial access, then install a malicious .msi file to get SYSTEM.

A medium Windows box from HackTheBox, get initial access by resetting the password of another user on a site with CSRF, then get creds by logging in as them that allow you to get a reverse shell and escalate to administrator by finding creds in an instance of bash for windows.