Nienor, may I ask you to post a couple more pictures? I would like to see the entire tree and a close up of the base showing how it was planted.
Is this injury on the south or southwest side of the tree? It may very well be sunscald. However, I would not have described this as a fatal flaw. How old is this tree and how big? The trunk caliper looks to be in the 4" range (guessing here so please correct me).
It is a good idea on thin barked and young trees to protect their trunks during the winter months to prevent sunscald. You may want to do so next season to prevent further damage.
Sylvia