I think somebody telnet to your server and try GET documents from other
server
Try telnet to your server:
telnet YOURSERVERHOST 80
And paste text in brackets (with empty line):
{{{
GET http://maps.yahoo.com/ HTTP/1.0
Connection: close
}}}
and check your logs
Posted at Nginx Forum: http://forum.nginx.org/read.php?2,189426,190883#msg-190883