Although many of the antivirus companies are kind enough to provide us with the free online virus scanner tools, yet many other antivirus vendors do not provide such a tool. Fortunately, there are three free online services which let you scan a file for malware using all the antivirus engines. These three services are Jotti’s Malware Scan, VirScan and VirusTotal. All of these three services are free and provide the same basic tool to upload a file to scan it for malware.
1. Jotti’s Malware Scan
Jotti’s malware scan is a free online service that enables you to scan suspicious files with several anti-virus programs. Scanners used are Linux versions and the detection differences with Windows versions of the same scanners may occur due to implementation differences. There is a 25 MB limit per file.
You can visit Jotti’s malware scan page at http://virusscan.jotti.org/. Then click on the Choose File button to choose a file from your hard disk that you want to scan for malware. Then click on the Submit file to upload and let the scanning start. After a few seconds, you would see the results.
VirSCAN.org is another free online malware scanning service which can scan your uploaded file with more than 35 antivirus engines. On uploading files you want to be checked, you can see the result of scanning and how dangerous and harmful (or harmless)for your computer those files are. There is a 20 MB file size limit per file. You can archive more than one file into a ZIP/RAR archive. Total number of files inside the ZIP/RAR archive should not exceed 20. You can also set the password of the archive as “infected” or “virus”.
You can visit VirSCAN.org page at http://virscan.org/. Click on the Choose File button to choose a file from your hard disk that you want to scan for malware. Then click on the Upload to upload and let the scanning start. After a few seconds, you would see the results.
VirusTotal is a very well known and free online malware scanning service. Just like Jotti and VirSCAN, you can upload files to VirusTotal and scan suspicious files with several anti-virus programs. VirusTotal was originally developed by Hispasec Sistemas but is not acquired by Google. It analyzes suspicious files and URLs enabling the identification of viruses, worms, trojans and other kinds of malicious content detected by antivirus engines and web analysis toolbars. There is a maximum file size limit of 64 MB. You can choose to send files over SSL (encrypted connection). You can also email the file you want to scan to VirusTotal.
You can visit the VirusTotal web page at http://www.virustotal.com/. Click on the Choose File button to choose a file from your hard disk that you want to scan for malware. Check the checkbox labeled Send it over SSL if you want to send the file over an encrypted connection. Then click on the Send file to upload and let the scanning start. After a few seconds, you would see the results.
You can also email the suspicious file to VirusTotal (but why would you do that if you can just scan it over the web interface). To send the email, create a new email message with SCAN as the subject, attach the suspicious file and send it to email@example.com. You should not attach a file more than 64 MB in size. After few minutes, you will receive a message containing the scan report from VirusTotal.
These online malware scanners let you scan suspicious file and help you find out if a file is really infected. You can use them to get a second opinion about a file, to check if your antivirus solution is not giving a false positive. You can use them to scan a file that looks suspicious to you but your antivirus solution is not detecting it as a malware. But you have to remember that these online scanners cannot replace a stay-resident desktop antivirus solution which protects continuously each time you access a file or visit a web site.