Which feature(s) are causing my C# application to be detected as a virus?

Question

I have developed an application that does the following:

(Using System.IO) Create, modify, and delete files

(Using DotNetZip) Extract downloaded zip files

(Using System.Net) Download files from a private server

(Using System.Reflection) Extract embedded dll and exe files onto the application's directory.

(Using System.Diagnostics) Start external processes such as the browser, and FontReg.exe for registering system fonts (is also the same file embedded into the application)

Many of these features can run on application startup. Which one of these (or all?) are causing the application to be detected as a virus, specifically a trojan? My guess is the embedding of another exe is the major one.

Avast and windows defender (at least the ones I know are) detect it as a trojan. Windows defender says it is a Trojan: Win32/Spursint.F!cl https://www.microsoft.com/security/portal/threat/encyclopedia/entry.aspx?name=Trojan%3AWin32%2FSpursint.F!cl&threatid=2147717281&enterprise=0

Answer 1

I figured out the issue. I was having it download direct exe files using system.net, which under many antivirus and malware programs would detect it as a virus. Simple solution was to put the exe in a zip and download it that way.