I looked at the ingredients of pestos at a local supermarket and found one out of a dozen that didn't have rapeseed or sunflower seed oil – they are included in so many groceries that aren't raw ingredients that they are really hard to avoid here if you don't pay attention or make everything from scratch.

Olive oil is alright if its extra virgin (cold pressed), because it has much more monounsaturated fat which is chemically more stable against oxidization than polyunsaturated ones.