Needy trojan family consists of trojans thatare written in
Java and use vulnerability in Microsoft Internet Explorer
Java Runtime. Usually these trojans change Internet Explorer
homepage and search settings and some variants also download
executable trojans.
This variant Needy.J changes Internet Explorer start page
and search settings to adult sites and downloads trojan executable.
The Needy.J is activated when a web site containing the
trojan is loaded with unpacthed Microsoft Internet Explorer
browser. When the JAR file containing the trojan is executed
it uses Microsoft Internet Explorer VerifierBug vulnerability to get
full privileges by escaping the Java security, and execute its
code.