The infected computers will then create and open backdoors on the companies' networks, which will allow the hackers to illegally gain access. Once the hackers have access to the companies’ networks, they can delete files, modify records, steal information, make files unreadable by encrypting them and then demand a ransom to restore them, or even shut or take down the companies' networks.
What are Macros?
Macros are a set of scripted instructions that can be used to automate simple or complex tasks in Microsoft Office (Excel, Word, and Outlook).
Right after Microsoft created Macros for Microsoft Office over a decade ago, cyber-criminals started abusing this useful tool, by using it to download and infect their victims’ computers with viruses, Trojan horse and other malware. That is why Microsoft decided to disable Macros by default and gave users of Microsoft Office the option of enabling or disabling it.
How to Protect Yourself against Malicious Macros
Fortunately, the strategy for keeping yourself free of macro malware or malicious Microsoft Office documents is a simple one: don’t enable Macros or “Enable Content.” Microsoft Office will warn you if you’re about to open a document that contains a Macro, and will give you the option of enabling or disabling it.
If a document with Macros came from anyone other than your I.T department or a highly trusted source, do not enable Macros for that document.