malformed vs misshapen

malformed and misshapen both are adjectives.

Word	Noun	Adjective	Verb	Adverb
malformed	No	Yes	No	No
misshapen	No	Yes	No	No

As adjectives, malformed and misshapen are synonyms defined as:

Other synonyms of malformed include deformed, distorted, ill-shapen.

malformed (adjective)	misshapen (adjective)
so badly formed or out of shape as to be ugly	so badly formed or out of shape as to be ugly