Finland being considered the victor of the Winter War would be a hilarious act of copium if it wasn't for how widespread of a belief it is, which makes it just plain sad. Finland lost its second largest city after the war. Imagine how it would be if in a war your country lost its second largest city (Los Angeles for the USA, Birmingham for the UK, Hamburg for Germany...) and think if there would be any way you could ever twist that in your imagination as a victory.
It would be like getting out of a street fight having lost a leg and claiming that you won because you could have lost both and because your adversary got really tired by the end of the fight.