Hackers have launched a malware blitz that poses as a 4 July greeting card.

Malicious emails, distributed worldwide, claim prospective victims have been sent an email greeting card, which they can view by clicking a link online. Varied subject lines based on US Independence Day are used to bait the ruse.

Users duped into clicking on the link within the infected email are taken to compromised sites hosting exploits that attempt to load a copy of the Storm Trojan onto vulnerable Windows PCs. The latest spam campaign is being launched from compromised machines, which have been turned into malware spewing spam bots.

The Storm Trojan, which first appeared in January 2007, uses a variety of eye-catching fake headlines to tricks users into visiting maliciously-constructed websites, a tactic that proved depressingly effective and has made the malware strain a major problem over recent months.

As before, users are advised to maintain up to date security software and avoid the temptation to visit links sent in unsolicited emails. ®

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