matscan is a project that scans the IPv4 space for Minecraft servers. It sends a Minecraft server list ping packet to every IP and port that it thinks has a chance of having a Minecraft server on it, which is why you might still see this website's address in your logs even if you're not running a Minecraft server.
There is also a secondary function to the scanner, which is automatically joining Minecraft servers that appear to potentially be incorrectly made public (without a whitelist) and warning them that they are vulnerable of being griefed. See my FAQ for more info about that: matdoes.dev/matscan.
My database is not public, nor does the scanner cause harm to any servers. If you'd like to contact me (mat), you can do so through Matrix (@mat:matdoes.dev) or email (matscan@matdoes.dev). My website is matdoes.dev.