weakness vs misfortune

weakness and misfortune both are nouns.

Word	Noun	Adjective	Verb	Adverb
weakness	Yes	No	No	No
misfortune	Yes	No	No	No

As nouns, misfortune is a hypernym of weakness; that is, misfortune is a word with a broader meaning than weakness:

Other hypernyms of weakness include bad luck, ill luck, tough luck.

weakness (noun)	misfortune (noun)
the property of lacking physical or mental strength; liability to failure under pressure or stress or strain	unnecessary and unforeseen trouble resulting from an unfortunate event
powerlessness revealed by an inability to act	an unfortunate state resulting from unfavorable outcomes
a penchant for something even though it might not be good for you
a flaw or weak point
the condition of being financially weak