Websites: VirusTotal

VirusTotal is a great online virus scanner, a Google subsidiary.
You can either scan a local file, or submit a remote URL; you can also search the database by file hash (SHA256, SHA1, MD5 etc.).
There's also a rating system for registered users.
Warning: all files you try to scan using this online service are actually get uploaded onto the remote server (or "cloud") for scanning, and subsequently can be shared with antivirus software developers in the future, so you should avoid scanning any confidential documents with this service ;-)
By uploading new malware, we can somehow improve the contemporary anti-virus solutions!

Links:

• home page,
  • currently, loading some kind of Web-2.0-styled uploader;
• rather old-style home page (unfortunately, apparently discontinued).

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Last updated: 2019-04-24