These words have different meanings.
Misinformation is an old word meaning incorrect or inaccurate information:
In the popular press there is much misinformation about the mechanics of gene expression.
Disinformation is a newer word meaning information intended to deceive.
Persuading the population of the need for war would require both crude and sophisticated forms of disinformation.
Misinformation arises from ignorance; disinformation is designed to mislead. Misinformation might therefore be considered the lesser of these two evils – if that’s not too strong a word – because unlike disinformation it does not imply deliberate duplicity. Both terms are associated with propaganda, disinformation especially so.