I just noticed that the ThumbnailLength value is also wrong by 0x50 bytes, so the ThumbnailImage is truncated but otherwise the image is OK after this repair.

But this gives us a clue as to why the image is corrupted. The originating software got the size of the ThumbnailImage wrong, so it calculated the size of the APP1 segment incorrectly (it thought it would be 0x50 bytes smaller than it actually was). So this was definitely a software bug, and not a problem with a file transfer corruption.

- Phil