VirusTotal is a malware detection service. It runs an aggregate of scanners and antivirus engines to provide analyses of potentially harmful files and sites. Users can upload files or submit URLs to VirusTotal to be scanned for worms, viruses, trojans, and more. VirusTotal also maintains a blacklist of files and URLs known to be harmful. The VirusTotal API exposes the information generated by its scanners to developers for integration and third-party access. The API is REST-based and returns JSON-formatted data.