What did Satan want with moses body?
USCCB NAB commentary says:
 a reference to an incident in the apocryphal Assumption of Moses. Dt 34:6 had said of Moses, literally in Greek, “they buried him” or “he (God?) buried him” (taken to mean “he was buried”). The later account tells how Michael, who was sent to bury him, was challenged by the devil’s interest in the body. Our author draws out the point that if an archangel refrained from reviling even the devil, how wrong it is for mere human beings to revile glorious beings (angels).
Haydock commentary says:
Ver. 9. When Michael, &c. We do not find this in any other canonical Scripture, so that St. Jude must either have had it from some tradition among the Jews, or from some writing which he, by the Spirit of God, knew to be true. It is not expressed on what account this *dispute *or strife was, betwixt St. Michael and the devil, about the body of Moses. The common interpretation is, that St. Michael conveyed the body of Moses out of the way, and from the knowledge of the Israelites, lest they should pay to it some idolatrous worship; whereas the devil, for that end, would have it buried, so that the people might know the place and adore it. See Deuteronomy xxxiv. 6. where it is said, “and no man hath known of his sepulchre until this present day.” (Witham) — Contended about the body, &c. This contention, which is no where else mentioned in holy writ, was originally known by revelation, and transmitted by tradition. It is thought the occasion of it was, that the devil would have had the body buried in such a place and manner, as to be worshipped by the Jews with divine honours. — Command thee, or, rebuke thee. (Challoner)e. (Challoner)
I think Robert Witham answers it well which is found in the Haydock Bible. I will give an additional note on this from the Aquinas Study Bible concerning Jude's use of a non-canonical writing.
Jude makes use here of the apocryphal book of the Assumption of Moses, but it does not mean that the book is inspired, but it does mean that the portion that Jude is referring to is true and worthy to be believed as inspired because Jude, who was lead by the Holy Spirit in this epistle, made reference to it, and in turn it becomes a divinely revealed fact in Scripture. There are numerous apocryphal writings that are intermingled with truth and exaggerated pious legends.* (John Litteral)* We even find St. Paul quoting some true passages from Pagan authors, and having been quoted by him, the quotes have all the authority of divinely inspired Scriptures (Titus 1:12; 1 Cor 15:33). (Bishop John McEvilly) If Michael had scruples about using an abusive word to the Devil, how much more insufferable is the action of those who are not afraid to revile people pre-eminent in authority and rank. (Erasmus)