Oil near catalytic converter

So it looks like there is some sort of sludge behind the engine near the cat. i have attempted to find where the leak is but still with no success. IT seems to be oil leaking in a very exact area iam at work so cant do any pics right now. but anyone else ever had oil leak there. I know that the coolant flange might be responsible but i dont think it is because the sludge appears to be oil.

You got a 1.8T or 3.0?

1.8