Another consideration is the camera's built in lens profiles - they also attempt to correct for vignetting. I don't think they do anything in raw, though.
I discovered something interesting about many raw converters - including Adobe's. It appears that parts of the raw converters (i.e. components of the software) come from the camera manufacturers, and in some cases these modules do some image corrections on their own - even if you turn all corrections off. DXO, on the other hand, appears to do everything themselves. I have a Canon S100 I use as my pocket camera. Pictures taken at the widest angle setting appear to have moderately high distortion when Adobe's lens correction is turned off. When processed with DXO with corrections turned off distortion and vignetting are so severe that significant portions of the image are black and the image is considerably wider angle and more distorted than it is with Adobe. This means that in some cases when you think image corrections are completely turned off, they may not be - that certainly is the case with the Canon S100.
Interestingly, with my S100 lens distortion is not symmetrical - vignetting and distortion are more severe on the left side of the image - which may be why they do some correction under the covers. With Adobe raw distortion and vignetting appear symmetrical when all corrections are turned off. Image files can contain lens distortion profile metadata - there is a standard way to do that. Maybe Canon calibrates each S100 camera - who knows? Strange but true