The secondary impact is to the sites targeted by the DDoS agents. Sites
undergoing a DDoS attack may experience unusually heavy traffic volumes or high packet
rates, resulting in degradation of services or loss of connectivity altogether.
III. Solutions
Home users
Run and maintain an anti-virus product
The malicious code being distributed in these attacks is under
continuous development by intruders, but most anti-virus software
vendors release frequently updated information, tools, or virus
databases to help detect and recover from the malicious code involved
in this activity. Therefore, it is important that users keep their
their anti-virus software up to date. The CERT/CC maintains a partial
list of anti-virus vendors at
http://www.cert.org/other_sources/viruses.html#VI
Many anti-virus packages support automatic updates of virus definitions.
The CERT/CC recommends using these automatic updates when available.
Do not run programs of unknown origin
Never download, install, or run a program unless you know it to be
authored by a person or company that you trust. Users of IRC and IM
services should be particularly wary of following links or running
software sent to them by other users, as this is a commonly used method
among intruders attempting to build networks of DDoS agents.
Understand the risks
Users are encouraged to review our "Home Network Security" tech tip,
which provides an overview of risks and mitigation strategies for
home users.
http://www.cert.org/tech_tips/home_networks.html
Sites
Site administrators are encouraged to review our report on denial of service
attack technology trends, as well as our recommendations for managing the threat
of denial-of-service attacks.
Trends in Denial of Service Attack Technology
http://www.cert.org/archive/pdf/DoS_trends.pdf
Managing the Threat of Denial-of-Service Attacks
http://www.cert.org/archive/pdf/Managing_DoS.pdf
Author(s): Allen D. Householder
This document is available from:
CERT/CC personnel answer the hotline 08:00-17:00 EST(GMT-5) / EDT(GMT-4)
Monday through Friday; they are on call for emergencies during other
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We strongly urge you to encrypt sensitive information sent by
email. Our public PGP key is available from
If you prefer to use DES, please call the CERT hotline for more
information.
CERT publications and other security information are available from
our web site
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* "CERT" and "CERT Coordination Center" are registered in the U.S. Patent and Trademark Office.
Copyright 2002 Carnegie Mellon University.