Wanted to change the oem foglights bulb to led, does anyone know what bulb is fittet to the foglights?

Check the manual. I think it’s an H8. I think it’s hard to access to replace, but if you do, please go in front and check the light doesn’t dazzle other road users. Here in Australia you find lots of uneducated idiots who put LED lights in refractive casings designed to house halogen bulbs and the result is to dazzle other road users. It’s incredibly obnoxious, annoying and just makes your car look cheap. I don’t think you can just swap them but if you have the right success pls share, I’d consider doing it too. 

Don't. You want a softer yellower light in fog and snow. White LED light will just reflect back making driving in for snow much worse. 

You can buy that model Osram H8. I am using that one. If you have error code for fog lamb you can adaptation by OBD or VCDS.