The increase can be attributed to
smarter hackers and better technology,
but the real driving causes behind the
increased zombie trend are better spam
filters and anti-spam laws. According to
Tom Spring at PC World Magazine,
"spammers are hiring virus writers and
hackers to help them create armies of
zombie PCs to send spam." This union of
hackers and spammers has been beneficial
to both parties in opening new revenue
steams that are extremely difficult to
shut down.
Gregg Mastoras, a senior security analyst at the security firm Sophos says,
"A new underground economy is evolving." This new economy is for the most part
illegal and to date impossible to stop completely.
As of late the Chinese hackers have thrown their hat into the game and have
taken the zombie computer business to the next level. Senior Pentagon Advisor
Paul Strassmann recently said, "As of September 14th 2007 there were exactly
735,598 computers in the United States infested with Chinese zombies".
Large groups of zombie computers can be used to form a "botnet" or network of
slave computers. This network can be used to send out millions of spam mails in
a short period of time. Slave networks are also used to commit a DoS attack. DoS
attacks, or Denial of Service, target a particular website and overwhelm the
server with information requests until the server can no longer handle the load.
These attacks or in no way secretive, and once discovered are easily shut down.
There will be a period of time however when site traffic will be disrupted by
the DoS attack. Larger more sophisticated networks such as those used by
governments or large firms have defensive measures in place to prevent damage
from a DoS attack.
