List of Unix binaries that can be used to bypass local security restrictions
Most of them by very far rely on <i>sudo</i>.  I've got a system without <i>sudo</i>.  The only way to execute something as root on my system is to log in, using a U2F security key, from a second system (typically a small laptop sitting next to my workstation).  That second system is connected to my workstation on a dedicated LAN only used by these two machines.  Firewalls on both (for example my workstation only allow SSH in from that one LAN and only from the IP of my laptop on that LAN etc.).  The laptop has no Internet access, WiFi disabled (modules prevented from loading, firewall preventing network access, etc.).  The laptop's sole purpose is to run command as root on the workstation: it's its sole purpose.<p>The downside is that I allow "root SSH", contrarily to every single best practice out there.  The upside...  Well.  Is that there's no "sudo" installed on my workstation.<p>I think no sudo even installed on the machine beats the "never allow root SSH" mantra but YMMV.<p>(to set up the system I install the system offline, from a Debian installation medium whose checksum and signature I've verified, do my thing as root on the workstation, set up the login using U2F from the laptop, then I "lock myself out" from login as root directly at the workstation by entering a password so long I'll never enter it, something like <i>"neverenterthisrootpasswordanymoreusethelaptopu2fkeyinstead#$bey8rUtIopTY6"*.  A bit of pain to enter twice but then I'm good to go)</i>