There are two fairly common options for (using) Wake On LAN. You either have it enabled and use the magic packet to wake up the PC or you don't. In Windows, this option is represented by the Allow this device to wake the computer and Only allow a magic packet to wake the computer checkboxes in Network Adapter Properties. Generally you would want to either check both or uncheck the "parent" one (which understandably disables the second option, too).
I am, however, interested in the last, not so common combination:
I noticed that using this option makes my PC wake up randomly overnight. Not every time, just sometimes, usually around 3am... And it got me thinking what exactly are those packets that can wake the PC up. I'd like to know whether they are potentially malicious, and to find their source.
I'm asking here because I couldn't find any documentation on this (everything I could find focuses on just the magic WoL packet). And I'm certain that it's caused by the network card because Windows shows this in the event viewer.
Please note that while my example is using Windows I'd also love to know whether this works the same on Linux and if not what differences are there.