All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
It is permissible to destroy or throw this CD with the intention of changing evil, and one is not sinful for doing so nor will there be liability on him. The Prophet said: "Whoever amongst you sees an evil, he should change it with his hand (i.e. physically).'' [Muslim].
Ibn Taymiyyah said: ''It is permissible to destroy something that is evil in itself [like intoxicants] or things which are not evil in principle but rendered evil [like the case of this CD onto which pornographic films was recorded]; this is what Imaam Ahmad and scholars of the Maaliki School of jurisprudence, and others have stated. Their evidence is what is confirmed from 'Umar that he ordered a shop which was selling intoxicants to be burnt, and this shop belonged to Ruwayshid Ath-Thaqafi, and told him "You are a Fuwaysiq and not Ruwayshid [Fuwaysiq denotes a dissolute person, whereas the name Ruwayshid denotes a judicious person]. Similarly, 'Ali ordered a village to be burnt as it was selling intoxicants, and this is narrated by Abu 'Ubaydah and others".
Therefore, if it is possible to erase the pornographic films which the CD contains and instead record some beneficial lectures on it and return it to the owner, as Allaah may guide him, then this is more appropriate. You should not destroy this CD if destroying it leads to a greater harm than leaving it for its owner; this is in order to avoid the greater of the two evils. Moreover, you should admonish the owner of this CD if you know him, and clarify to him the religious ruling about these films and its bad cosequences on its owner.
The Prophet said: "The (essence of) religion is advice." The companions inquired: ''To whom, O Prophet of Allaah?" He replied: "To Allaah, His Book, His Prophet, and to the leaders of the Muslims and the common Muslim people." [Muslim].
For more benefit, please refer to Fatwa 82737.
Allaah Knows best.