Definition
A macro virus is a malicious program that spreads through contaminated macro-enabled files such as those found in Excel and MS Word. The malware infects your device by executing a harmful code, which compromises private data.
Examples of Macros Virus
- Melissa: This virus emerged in 1999, spread through email, and targeted MS Word documents. Once active, it could send itself to the first 50 contacts in the victim’s address book.
- Babyk: It infected Word documents and spread from one user to another through email using the victim’s Outlook address book.
Preventing Macro Viruses
- Refrain from opening suspicious email attachments and links.
- Set the security level to allow macros from legitimate sources only or disable macro support entirely.
- Update your antivirus software regularly.
How a Macro Virus Works and Spreads
Macro virus spreads through phishing emails that contain malicious links and files. As users share the infected files, the malware infiltrates the victim’s device after clicking on the link or downloading the attachment.
Other Ways Macro Viruses May Spread:
- Sharing files over a network.
- Storing infected files on a removable disk and sharing it with others.
- Downloading a malicious file using a modem and opening it.
- Downloading an infected file from the internet and opening it.
What Can Macro Viruses Do?
Macro viruses can do the following:
- Cause strange activities in a document, such as deleting or adding words.
- Create new files.
- Corrupt stored data.
- Format hard drives.
- Access private email accounts.
- Share copies of malicious files to other users in the contact list.
Evolution of Macro Viruses
Due to their robust macro languages, macro viruses initially focused on infecting Word and Excel documents, primarily targeting the Windows operating system. Over time, macro viruses expanded to affect various applications, files, and operating systems.
They became cross-platform, capable of infecting both Windows and Mac computers using the same code.
In 2017, MacDownloader emerged as the first Word macro virus for macOS. MacDownloader allowed hackers to exploit malicious macros in Word documents to install malware on Mac systems. The malware aimed to steal sensitive user data, including browser history logs, webcam files, passwords, and encryption keys.
Macros Virus Symptoms
A macro virus can manifest itself through:
- A pop-up requesting you to enable macros.
- Device running slow.
- Strange error messages.
- Documents are saved as template files.
- Password requests on files which don’t require passwords.