Security → netstat question

Did you include the command switch to check what executeable(s) it may be associated with?

If this is Windows, dollars to donuts this is the Windows Shares listener --

It's UDP (listening) port and as such, it's connectionless (comparing to TCP, which has two connection ends). UDP packet could be sent to any address. Thus, the "Foreign Address" is always unknown (in other words, it could be any), which is indicated here as *.*.