We all know that downloading suspicious files is a good way to expose your device to a virus, but as hackers get smarter, the ability to easily detect a harmful file gets harder. Hackers have learned how to disguise a file to seem harmless by changing or hiding the file extension.
How are hackers hiding the files?
A file extension is the code at the end of a file that helps us identify the type of file it is. Some extensions are “.mp3”, “.pdf” but the most common extension is “.exe” which is the file extension for programs, and unfortunately viruses as well.
Hackers have many ways of hiding “.exe” in the file name, and the easiest way is already done for them. Windows naturally hides file extensions to make the title look cleaner. For hackers this is great news because they can essentially call the file anything they want and chances are high you won’t ever see the extension.
Another way hackers can go about hiding an extension is by using a specific software that reverses the name of the file. This allows them to send you a virus that looks like a harmless file, but really contains a virus. For example, they can send you a virus called “fdp.exe” and it will show up on your computer as “exe.pdf”, making you think it’s just a PDF, and therefore more likely to download it.
Now, there are ways to spot files containing viruses:
- Pay attention to and know the meanings of different file extensions
- Make sure you’re using a good security software
- Change Windows default to show file extensions
- Here are Microsoft’s instructions on How to Show File Extensions in Windows Explorer
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