According to Symantec, the malware in question is called Trojan.Pidief.A and comes packed withing a specially crafted .pdf file. If the unsuspecting user opens the file, then an executable named ldr.exe will be automatically downloaded on the computer.
The security company warns users to be extra careful with emails that have "invoice", "statement" or "bill" as subject and only contain the .pdf file. Up till now, there malicious files bear one of the following names:
It appears that the new spam campaign targets specific business organization, Symantec added.
The good news is that the Adobe vulnerability already has a patch. Adobe Reader users can download it from here, while the update for the Acrobat is located here.