For more details you can
refer the following article
<st1:place w:st="on"><st1:city w:st="on">Worms</st1:city></st1:place> and threats that spread across networks by network
shares have become more common in recent years.--Like Downadup/Conficker
https://www-secure.symantec.com/connect/articles/worms-and-threats-spread-across-networks-network-shares-have-become-more-common-recent-yea-0