Trend Micro security experts have not seen pump-and-dump spam campaigns in a fairly long time. In fact, some of the most recent attacks of this kind were last seen last year:
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Taking Stock of Spam
In a pump-and-dump attack, spammers raise the stock prices of companies they own shares in by sending spammed messages with misleading or outright untrue positive news about the said companies. Once the companies’ real stock prices have sufficiently risen, the spammers will then sell or dump their own shares to gain profit.
TrendLabs engineers, however, recently saw the recent comeback of this tactic hit the popular VoIP application, Skype. Spammers used the application’s instant-messaging (IM) feature to send the pump-and-dump spammed messages.
Spammers tried to promote two companies—EcoBlu Products, Inc. and Terra Energy & Resource. Like other spam runs using IM applications, Skype users received these email messages from users who were not in their lists of contacts.