The last one, spotted by GFI Software, tries to reel in the users of Intuit's QuickBooks - accounting software marketed to small business owners - with an offer of free shipping when ordering tax forms:
Unfortunately for the recipients who click on them, the embedded links lead not to the ordering form, but to a page that shows a "Connecting to server…" message and eventually redirects them to another page hosting the Blackhole exploit kit.
If the kit manages to exploit any of the security flaws is was designed to, the victim is silently infected with malware.
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