Hoax-Slayer warns that with the USPS logo, delivery bar code and shipping numbers, the spoofed notification certainly looks rather legitimate:
Unfortunately, it's not, and the link that will supposedly take you to the shipping label that you are urged to print out and take to the nearest "UPS" office will actually lead you to a compromised website that will automatically download a file named Shipping_Label_USPS.zip.
The file contained in it is a downloader Trojan that at the time when the spam campaign was first spotted had an extremely low detection rate.
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