Are only evil jinns capable of possessing or do Muslim or good jinn possess too?

In most cases it is the evil jinn that possesses. They are forbidden to enter into our world and to affect us, but in some cases, it may involve some jinn who is not in himself evil, but as explained by some scholars; the fact that the jinn tend to be more rash in their actions, so they don’t necessarily have the patience and reasoning power of human beings, so they may react to something that human being may have done to harm them as a response by affecting somebody.

With regard to the jinn harming humans, this is proven to happen and it does happen. Protection against that is attained by reciting Qur’an and adhkar (dhikr) prescribed in Shari’ah.

Shaykh Ibn ‘Uthaymeen (rahimullah) said: “Undoubtedly the jinn can have a harmful effect on humans, and they could even kill them. They may harm a person by throwing stones at him or by trying to terrify him.”

There are other things that are proven in the Sunnah or indicated by real events. It was reported that the Messenger (ﷺ) gave permission to one of his Companions to go to his wife during one of the military campaigns – I think it was the campaign of al-Khandaq – as he was a young man who had recently got married. When he reached his house, he found his wife standing at the door, and he objected to that. She said to him, ‘Go inside,’ so he went inside and found a snake curled up on the bed. He had a spear with him, so he stabbed it with the spear until it died, and at the same instant as the snake died the man also died. It was not known which of them died first, the snake or the man.

When the Prophet (ﷺ) heard of that, he forbade killing the harmless kinds of snakes that are found in houses, apart from those which are maimed or are streaked and malignant.

This indicates that jinn may attack humans, and that they may harm them, as is known from real-life events. There are numerous reports which indicate that a man may come to a deserted area, and a stone may be thrown at him, but he does not see anybody, or he may hear voices or a rustling sound like the rustling of trees, and other things that may make him feel distressed and scared. A jinn may also enter the body of a human, either because of love or with the intention of harming him, or for some other reason. This is indicated in the ayah:

“Those who eat Ribaa will not stand (on the Day of Resurrection) except like the standing of a person beaten by Shaytaan (Satan) leading him to insanity.” [1]

 In such cases, the jinn may speak from inside of that person and address the one who is reading verses from the Qur’an over him; the reciter may take a promise from the jinn never to come back. They are other things reported which are widespread amongst the people.

So the protection which will prevent the evil of the jinn is for a person to recite that which is narrated in the Sunnah as being effective in providing protection, such as Aayat al-Kursi, “For if a person recites Aayat al-Kursi at night, he will continue to have protection from Allah, and no shaytaan will come near him until morning. And Allah is the Protector.’” [2]

If they are called upon and the Qur’an is being recited, etc; and if they are told to leave they will leave and they tend to leave more easily. So it is easy to handle them, where as when it involves a disbelieving or evil jinn, it becomes more difficult to handle and make them leave.

The Sunnah mentions adhkhar (dhikr) by means of which one may gain protection from the shayaateen (devils). These include:

Seeking refuge with Allah from the jinn

Allah says:

“And if there comes to you from Satan an evil suggestion, then seek refuge in Allah. Indeed, He is the Hearing, the Knowing.” [3]

“And if an evil whisper comes to you from Shaytaan (Satan), then seek refuge with Allah. Verily, He is All-Hearer, All-Knower” [4]

It was narrated from Sulaymaan ibn Sard that two men were trading insults in the presence of the Prophet (ﷺ), until the face of one of them turned red. The Prophet (ﷺ) said, “I know a word which, if he were to say it, what he is suffering from would go away: ‘A’oodhuBillaahi min al-Shaytaanir-rajeem (I seek refuge with Allah from the accursed Shaytaan).’” [5]

Source: http://islamqa.com/en/ref/10513/jinn

References:

[1] Surah al-Baqarah, 2:275

[2] Majmoo’ Fataawa al-Shaykh Ibn ‘Uthaymeen, 1/287-288

[3] Surah Fussilat, 41:36

[4] Surah al-‘Ara’f, 7:200

[5] Bukhari: 3108 and Muslim: 2610