In his October 2003 General Conference talk, "The Standard of Truth Has Been Erected," Boyd K. Packer said that:
Satan, with his
angels, will try to capture your thoughts and control what you do. If he can,
he will corrupt anything that is good.
In a footnote to this, Packer references
Luke 22:3:
Then entered Satan
into Judas surnamed Iscariot, being of the number of the twelve.
This shows that Packer did not hold the
really silly view that Judas was well-intentioned in his betrayal of Jesus, a silly
(and frankly, blasphemous) view some Latter-day Saints have forwarded.