An alleged Samsung Galaxy S9 has shown up in some leaked images from two different sources. Judging by the first set of images, one of which you can see above and the other which you can see in the gallery below as a close up of the first image, the design of the Galaxy S9 isn't too much different from that of the design on the Galaxy S8, save for the bottom bezel which appears more minimal on the alleged Galaxy S9 image. Moving beyond this one detail it looks like everything about the style of the device has been unchanged, at least from the front as the back of the device is not shown in any of the leaked images.
Another thing to point out is that the bottom bezel in the first two images and the bottom bezel in the second two images appear to be just as minimal as one another, lending a little bit of credence to the possibility that this could really be the design of the next Galaxy S flagship phone. While the device in the first two images appears to be Black, the device in the second two images has a Red color, suggesting that Samsung would be planning to launch the Galaxy S9 in Red or that it may have been playing with the possibility of launching it in this color. In the image of the Red device the top bezel is just as visibly thicker than the bottom one as in the first image from up above, and although the bezel design on the Galaxy S8 looked more symmetrical before, Samsung would have to keep the bezel on the top as thick as it is to keep room for the front-facing camera and other sensors that are there on the Galaxy S8.
The Galaxy S9 is rumored to make an appearance at CES 2018, though it's worth remembering that this has been the same story for the last couple of Galaxy S flagship phones, with rumors pegging the device as having a CES unveiling, only to be revealed later at Samsung's Unpacked event both at MWC or at its own event a little later on. That said, there's no guarantee that Samsung is gearing up to show off the phone at CES next year, and it's entirely possible that these leaks are not actually of the phone.