Inspecting Information from Built Unity Players

It can be useful to inspect information from built Unity players. This can be helpful to check whether a certain DLL is used by the game, or verify that the player built properly.

• [Android] .xapk/.apk/.so can be traversed with 7-Zip
• Unity asset file headers can be inspected with any hex editor¹⁾

Find this information in:

• .unity3d file header
• resource file headers, for example:
  • unity default resources
  • globalgamemanagers
  • level<number>
  • sharedassets<number>.assets
  • files with 32 characters long names using hexadecimal characters [0-9a-f]
• [Android]²⁾ lib/<arch>/libunity.so/.note.unity
• [Windows] <executable>/.rsrc/version.txt
• [Windows] UnityPlayer.dll - Properties / Details / File version

These methods work even with IL2CPP builds.

• ScriptingAssemblies.json
• Search for .dll in global-metadata.dat with a hex editor.

Use cases:

• We can determine URP usage by looking for Unity.RenderPipelines.Universal.*.dll³⁾

• In non-IL2CPP⁴⁾ builds, all code that made it into a build is also available to the end user and can be viewed with tools ⁵⁾ relatively easily. Obfuscation can mitigate this, however the most effective obfuscation methods⁶⁾ are not compatible with IL2CPP so can't be used by developers.
• global-metadata.dat appears to contain all the method/property/field names in UTF-8 (or at least those that were used and not stripped) from all the assemblies that were used by the build.