Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
Qur'an is Word of Allah, revealed to the Prophet Muhammad (Sallallahu Alaihi wa Sallam); it is an attribute among the uncountable Attributes of Allah. Allah has Spoken these words by sound and letters. Qur'an does not say but it is Allah Who ‘Says’.
Therefore, it is not among the good decencies with Allah to Say: “Qur'an says, or Qur'an said: “Since it might be misunderstood that Qur'an has an independent or a separate existence”.
If one uses such an expression with the intention that the Qur'an is a creature then he is disbelieving in an Attribute of Allah (May Allah protect us from that). If he does not mean it, it is better to avoid such an expression since it may raise misunderstandings.
Allah knows best.