Don't know much about it, except it describes a hopeless situation. In painting for instance, it's when a painter overworks the painting and makes a muddy looking mess.
Looked it up on Wikipedia and this is what it said:
FUBAR likely had its origins in the German word Furchtbar, meaning frightful, or terrible. It is pronounced with a soft cht, and probably made the transition during World War II because foo had been popularized in American culture, appearing in a 1938 Warner Brothers Daffy Duck cartoon and the comic strip Smokey Stover.
Electronics engineers say that snafu and fubar were used before the war by repairmen sent out to repair phone booths. They had to report the situation at arrival to the scene, often on a very bad line, so they developed these acronyms to make themselves understood.
Les
