Weird reflection artefacts on mesh imported from Zbrush?

Hi, I got this model from a client who has built it in Zbrush. View one is in Cinema4d, view two is in Unity with a basic material without textures or normals applied. Does anyone have an idea of what is happening here? Tested on Unity 2021 and 2020.

Exporting the model as fbx from C4D resolved the issue. Odd as I didn’t do any changes to it.