There are existing online services that can also aid us in our reversing.

• VirusTotal: This submits a file or a URL and cross-references it with a list of detections from various security programs. The result gives us an idea if the file is indeed malicious or not. It can also show us some file information, such as the SHA256, MD5, file size, and any indicators.
• Malwr: Files submitted here will be submitted to a backend Cuckoo system.
• Falcon Sandbox: This is also known as hybrid-analysis, and is an online automated analysis system developed by Payload Security. Results from Cuckoo and hybrid-analysis uncover similar behaviors, but one may show more information than the other. This may depend on how the client sandbox was set up. If, say, the .NET framework was not installed in the sandbox, submitted .NET executables will not run as expected.
• whois.domaintools.com: This is a site that shows the whois information about a domain or URL. This may come in handy, especially when trying to determine which country or state a program is trying to connect to.
• robtex.com: A similar site to whois, that shows historical info and a graphical tree of what a given site is connected to.
• debuggex.com: This is an online regular expressions service, where you can test your regex syntax. This can come in handy when developing scripts, or reading scripts or codes that contain regular expressions.