Macrovirus (P): what is it?

A macrovirus is a malware which uses the macro command programming language used in office software to perform common actions. A macro virus is capable of altering these commands in order to be able to execute and threaten the integrity of the data.

What is a macrovirus?

You inquire about the definition of macrovirus ? This is a computer virus who uses the same language computer science than Office suite programs such as Microsoft Word and Excel. In practice, this malware exploits the macro-instructions (that is, predefined automations) used by users to actually execute a malicious command.

For example, an active macrovirus is capable of blocking the recording of files, of modifying their content, of controlling the storage of data, and even of destroying them.

Unlike other attacks such as ransonware where the spyware, macroviruses do not cause considerable damage such as data theft, they mainly harm the proper functioning of a work environment or generate a consequent loss of information. Their danger comes above all from the high probability of being distributed since a simple infected “.doc” or “.xls” file can corrupt other computers.

Because yes, as the famous Avast antivirus specifiesthe ” macroviruses target software rather than systems […] and can infect any operating system “. The holders of computer like from Mac can therefore see their software from office automation affected.

Microsoft software, privileged targets

Given their immense deployment in companies but also in individuals, Excel and Word office software are in the crosshairs of macroviruses.

Detecting the presence of macroviruses is not always easy without the use of a antivirus software or without the intervention of an expert. However, certain signals can alert you and lead you to think that your computer is behaving suspiciously:

• a sudden slowdown may be a sign that automations are going on without you realizing it;
• some of your files no longer open or so provided you provide a password that you have never entered before;
• documents and files cannot be found or are completely corrupted;
• some of your contacts inform you to receive dubious emails from you whereas you did not send anything.

Software from the Microsoft Office suite (Word, Excel, PowerPoint, etc.) are therefore the most targeted by macroviruses given their very large diffusion. By default, they activate protection against the execution of macroviruses, but no one is safe from an attack, hence the importance of remaining cautious. Some cybersecurity professionals have chosen to train in defense against macroviruses to support companies in the protection of their data and their workstations.

How are they distributed?

This kind of software malware can spread through tricked emails or URLs. Downloading infected attachments or transmitting corrupted documents through the use of key USB are among the most common spreads.

Here are some tips to minimize the risks. These are good reflexes to adopt to reduce attempts to cyberattacks. This concerns macroviruses, but also all other types of viruses deployed on a large scale:

• do not open a suspicious attachment. At best if you know the sender, ask him to confirm that it is indeed one of his shipments before clicking.
• same for links. If a link is sent to you by email, for example, you can hover with the mouse cursor (but without clicking) to see the destination URL at the bottom left of the screen. A web address with an unknown name or which multiplies the characters without any logic will most certainly turn out to be a dubious link.

Emails are a vector for the dissemination of mass. All you have to do is send an infected file for it to cause damage to your recipient’s computer.

The best known macroviruses

One of the macro virus the best known is called Melissa. It raged during the year 1999. It may seem a long time ago, but this attack remains one of the most widespread and serious in the category of macroviruses.

By exploiting certain features of Word 97 and Word 2000, the malware was running in the background via Outlook sending emails with the subject “Important message from…” and including a file attached to the first 50 contacts in the address book. In batches of 50 messages, the virus quickly spread.

Another concrete and more recent case: the first macroviruses intended for computers operating macOS. Very quickly detected, the latter could not do much damage to users. However, it seems that this macro virus checked for the presence of firewall and installed, in the event that it was not there, another malware intended to spy.

With less proportional risks than Microsoft devices, Apple devices are not fully protected against viruses and can also be the target of macroviruses!