*C# Dropper, D/Invoke Manual Mapping(ntdll.dll) + Shellcode Injection* After a really good talk by Jean-Francois Maes, I wanted to try his code’s functionality (EDRGoesBrrr) with a dropper that I’m working on. The dropper opens an HTTPS tunnel with ngrok, downloads an edited version of his injector which leverages D/Invoke to manually map ntdll.dll (avoiding any hooks) and then injects a Covenant implant into RDP clipboard monitor. I did use the NuGet package for D/Invoke which didn’t seem to cause any problems. No alerts in MDE but there was an informational warning in the timeline regarding the parent PID spoofing. Testing was done on MDE (BlockMode + Automated Investigation).
Talk (EDR Mechanics / Evasion Techniques): Defeating EDR's using D/Invoke - YouTube
EDRGoesBrrr(source):brown-bags/DInvoke to defeat EDRs/DemoDInvokeLoader at main · NVISOsecurity/brown-bags · GitHub