T1127.001: MSBuild

Summary

Adversaries may use MSBuild to proxy execution of code through a trusted Windows utility. MSBuild.exe (Microsoft Build Engine) is a software build platform used by Visual Studio. It handles XML formatted project files that define requirements for loading and building various platforms and configurations.(Citation: MSDN MSBuild) Adversaries can abuse MSBuild to proxy execution of malicious code. The inline task capability of MSBuild that was introduced in .NET version 4 allows for C# or Visual Basic code to be inserted into an XML project file.(Citation: MSDN MSBuild)(Citation: Microsoft MSBuild Inline Tasks 2017) MSBuild will compile and execute the inline task. MSBuild.exe is a signed Microsoft binary, so when it is used this way it can execute arbitrary code and bypass application control defenses that are configured to allow MSBuild.exe execution.(Citation: LOLBAS Msbuild)