How to protect
yourself against email-borne viruses
(continued)
III. Solution
1. Run and maintain an anti-virus product
While an up-to-date antivirus software package cannot
protect against all malicious code, for most users it
remains the best first line of defense against malicious
code attacks
2. Do not run programs of unknown origin
3. Do not download, install, or run a program unless
you know it to be authored by a person or company that
you trust.
4. Email users should be wary of unexpected attachments.
Be sure you know the source of an attachment before opening
it. Also remember that it is not enough that the mail
originated from an email address you recognize. The Melissa
virus spread precisely because it originated from a familiar
email address.
Users should also be wary of URLs in email messages.
URLs can link to malicious content that in some cases
may be executed without user intervention. A common social
engineering technique known as "phishing" uses
misleading URLs to entice users to visit malicious web
sites. These sites spoof legitimate web sites to solicit
sensitive information such as passwords or account numbers.
In addition, users of Internet Relay Chat (IRC), Instant
Messaging (IM), and file-sharing services should be particularly
careful of following links or running software sent to
them by other users. These are commonly used methods
among intruders attempting to build networks of distributed
denial-of-service (DDoS) agents.
5. Use a personal firewall
A personal firewall will not necessarily protect your
system from an email-borne virus, but a properly configured
personal firewall may prevent the virus from downloading
additional components or launching attacks against other
systems. Unfortunately, once on a system, a virus may
be able to disable a software firewall, thus eliminating
its protection.
We advise everyone to keep updating your antivirus software
and download the latest fixtool provided by Norman against
MyDoom. You can get the fixtool from this address:
http://www.norman.com/public/MyDoomFix.com
Source: CERT
|
