It’s an image within a gallery so there is the actual image and a thumbnail. Replacing the image is easy, creating the thumbnail is a hassle. Both of them look the same so my guess is that it has happened when the thumbnail was created or in some step before that.
The structure of the jpg is fine but the image itself is not as it looks like it has been trimmed.
That’s a clear indication of a “write error.” We see that most often with digital cameras, where for a variety of reasons, the card may not keep up with the camera’s write mechanism.
It’s possible that the underlying image data has always been compromised, as the small image you see in the Finder is usually taken from a thumbnail version of the image that’s also embedded in the full image container (.JPG etc).
So the first thing I’d do is go back to the original file and open it up with something sophisticated, such as Photoshop or Pixelmator Pro. If you see the same problem there, then the original you brought into the computer is corrupt (the card reader can also be a culprit in this). If you see the image looks fine in PS/PP, then you have to figure out where it corrupted during the various downstream writes that occurred (to Finder, Finder to Elements, Elements to server, etc.). Because if it happened once, it will happen again.
