This document is available from:
http://www.cert.org/advisories/CA-2004-02.html
I. Description
Over the past week, we have seen two more mass-mailing viruses,
W32/Bagle and W32/Novarg, impact a significant number of home users
and sites. The technology used in these viruses is not significantly
different from prior mass-mailing viruses such as W32/Sobig and
W32/Mimail. Unsolicited email messages containing attachments are sent
to unsuspecting recipients. They may contain a return address, a
provocative envelope, or something else that encourages its receiver
to open it. This technique is called social engineering. Because we
are trusting and curious, social engineering is often effective. The
widespread impact of these latest viruses, which rely on human
intervention to spread, demonstrates the effectiveness of social
engineering.
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Hector Santos, Santronics Software, Inc.
http://www.santronics.com