pharming.. dns cache insertion...

[bruce]

hi...

forgive me for what might be a basic/obvious question...

i've started seeing articles that talk about pharming, and dns insertion,
for use by hackers. can someone explain to me (or point to
articles/information that can) how someone can modify a dns server, aside
from physically/remotely accessing the server to insert/update information?

i must be missing something here....

thanks

bruce
bedouglas at earthlink.net