What characters are evil in scene 4 of Macbeth?

Each of the five acts in the play has a fourth scene—except act 4, which only has three scenes—so I'm not positive which scene 4 you are referring to.
In act 1, scene 4, we learn about the death of the old Thane of Cawdor, a terrible and disloyal traitor to the king. He could be described as evil. However, Macbeth is also starting to consider what he might have to do to become king, especially after Duncan appoints his older son, Malcolm, as the Prince of Cumberland: his heir to the throne. We might say that we can see the seeds of evil beginning to germinate here.
In act 2, scene 4, the Thane of Ross converses with an unnamed old man about all of the strange things that have been happening since Duncan was murdered. When Macduff joins them, they discuss the king's two sons, Malcolm and Donalbain, who are believed to have hired the chamberlains to murder their father, Duncan. Ross and Macduff might think of Duncan's sons as evil if they truly believe that the king's sons were responsible for his death.
In act 3, scene 4, we see the Macbeths' failed dinner party. In this scene, Macbeth is haunted by the ghost of Banquo, his best friend who he has recently had killed. If anyone is "evil" in this scene, it is Macbeth because he is the one deceiving his friends, and even his wife, pretending that he still expects Banquo to show up at the dinner when he knows full well that the man has been murdered. By the scene's end, he tells his wife, "We are yet but young in deed" (3.4.176). He means that they are going to have to keep committing crimes in order to hold on to their power and position. We might certainly see him as evil by now.
In act 5, scene 4, Malcolm leads his army toward Macbeth's castle. One of the Weird Sisters' prophecies, about Birnam Wood coming to Dunsinane Hill, comes to fruition in this scene when Malcolm has his soldiers carry tree boughs in front of them to disguise their numbers. Macbeth is referred to here as "the tyrant," though he does not actually appear in the scene.