Well… the answer could be yes! Opening a Zip file can bring viruses!
The very famous approach to send .exe file from one person to another through an email is to Zip it first, then email the resulting Zip, and then the receiver has to unzip at his end. That’s where the planning of hackers and spammers start to get materialized!
Why Spammers use Zip file to spread virus?
Zip file contain collection of files inside it. Simply knowing that you have a Zip file doesn’t tell you what resides inside. You really need to unzip it to look at the files that have been compressed. Due to this, the contents of Zip file are always hidden and unclear. This is the reason why hackers hack Zip files to spread viruses. Most of the potential hackers can even hack encrypted Zip files and spread virus; wherein you try to extract password protected Zip files contents and use the files without having mere knowledge about hacking.
Zip as unclear mystery
It is easy to double click an email attachment or a file within Zip file without knowing what lies under the mask. This is how your computer gets infected with potential malware when you actively make the virus to run, without realizing the file being double clicked could contain a virus.
But you can’t get a virus just by double clicking on a Zip file, as double clicking a Zip file has a different story!
When you get a Zip as an email attachment, double clicking that compressed file will just open it. If the file is a real Zip and it contains a malware, your computer will not get infected by virus until and unless you try to execute virus contained files. For instance, just assume you have a Zip file containing executable files along with virus inside it, called virus.exe. Under such case, double clicking just a Zip file doesn’t bring virus, but double clicking virus.exe will cause you to get virus.
From one of the forum users,
Is it possible to get virus just by trying to uncompress the Zip? Can Zip extension be manipulated so it is not actually a Zip file but a virus?”
Well, it is already said in the above part that a Zip file can contain virus, and in fact it is a common way of putting malware into a compressed file and spread virus. But the error message in the above scenario is not a symptom of virus or malware, but it is a standard error that you may receive when the file is either corrupted or if it has been incompletely downloaded.
Tip: You can know if compressed ZIP file contains any virus by knowing the file types that it holds. Follow the link here to have knowledge on potentially unsafe file types associated in ZIP.
Then how to know if Zip contains a virus?
When you double click an EXE file compressed within Zip file, WinZip will warn you in some situations with a message that you are working with a file type that may potentially bring viruses into your computer.
WinZip consider the file type that could harm your computer as “Potentially Unsafe File Types”. Here, EXE refers to potentially unsafe file type. Some of the other examples include, ADE, ADP, APP, ASA, ASP, BAS, BAT, CER, CHM, CMD, COM, CPL, CRT, CSH, DLL, EXE, FXP, HLP, HTA, HTM, HTML, HTR, INF, INS, ISP, ITS, JS, JSE, KSH, LNK, MAD, MAF, MAG, MAM, MAQ, MAR, MAS, MAT, MAU, MAV, MAW, MDA, MDB, MDE, MDT, MDW, MDZ, MHT, MHTM, MHTML, etc.
So be careful while extracting a Zip file compressed with any of the above mentioned file types. Remember, regardless of the file types involved, it is still possible to extract Zip file by ignoring the warning message or when the caution message is turned off, as a result your computer might get harmful viruses. Consequently, below security tips may help you in preventing viruses.
Better to know your source –
If you get any Zip attachments from Banks, governments, delivery services, the postal service, etc. remember all these companies should simply never send you a Zip file. The information they want to convey you will be either in the body of the mail, or they’ll tell you to log in to your account with their service directly.
Keep your system protected and Up-To-Date –
Zip files are incredibly useful, but due to spammers they have been used to trick you in installing malware. So it is worth always you keep your system protected by installing good antivirus software and update the system with new WinZip updates or maintenance releases.
To help in avoiding viruses or malware entering into your computer, you must be aware with the useful information provided on this article. A little knowledge on which possible file types are safe/unsafe and some sensible security tips will let you to be comfortable working with the Zip files that you receive.