The Australian Competition and Consumer Commission says it has received 1360 complaints and revealed that $80,000 was reported lost to the scams.
The ACCC says it has received more than 100 reports of this scam already this month, with a significant increase in both personal and commercial information loss being reported. It says this accounts for more than 350 reports this year, up from 250 in 2014.
"Scammers take advantage of the busy Christmas season to send you emails about a 'missed parcel delivery', purportedly from trusted services such as Australia Post or FedEx," says ACCC deputy chair Delia Rickard.
"The emails may be personalised with your name and address and look to be from a legitimate company complete with fraudulent logos.
"The email may mention a fee will be charged while they hold your undelivered item.
"Scammers ask you to open an attachment or download a file to retrieve your parcel. If you follow these instructions, an executable file (.exe) will load on to your computer and install ransomware as soon as it is opened."
Rickard says allows ransomware to be installed into the recipient's computer, which leads to a freeze on the computer and demands for a ransom to be paid to regain access to the computer.
"Scammers commonly ask for bitcoins or ask you to transfer money by wire transfer," she says.
"Even if you pay the fee, there is no guarantee that your computer will be unlocked.
"If you receive an email about a package, don't open any attachments or download files.
"Regularly back-up your computer's data on a separate hard drive. Follow these steps to protect yourself this Christmas."
The ACCC offers the following advice to protect against this scam.
Australia Post will put a notice in your letter box if a package was undeliverable. Delete any email claiming to be from Australia Post about an undelivered package.
Do not click on links or download files in emails you receive out of the blue, especially if they are executable (.exe) files or zip files. These files are likely to contain malware.
If you are suspicious about a 'missed' parcel delivery, call the company directly to verify that the correspondence is genuine. Independently source the contact details through an internet search or phone book, and don't rely on numbers provided.
Buy yourself (or your business) a stand-alone hard drive for Christmas. These have become relatively inexpensive and can save you a lot if your computer is infected by malware or ransomware.
Regularly back-up your computer's data on a separate hard drive. If your computer is infected by malware or ransomware you can restore the factory settings and easily re-install all of your software and data.
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