Is what was attributed to Sheikh Al-Sijistani in his book "Al-Masahif" correct, that Al-Hajjaj changed ten words in Uthman's Mushaf, and what is the truth about the existence of a book titled "What Al-Hajjaj Changed in Uthman's Mushaf"?

Doubt does not touch the authenticity of the Quran due to Allah's preservation of it. The Quran was compiled into a single book during the era of Abu Bakr Al-Siddiq, may Allah be pleased with him, after many memorizers (of the Quran) were martyred. Zayd ibn Thabit, may Allah be pleased with him, undertook the task, compiling it from parchments and the breasts of men.

As for the vocalization (تنقيط) of the Mushaf, Al-Hajjaj himself did not directly oversee it. Rather, Abd al-Malik ibn Marwan ordered it during his reign due to the expansion of the Islamic state and the mixing of Arabs with non-Arabs. Al-Hajjaj entrusted Nasr ibn Asim al-Laythi and Yahya ibn Ya'mur al-Adwani with vocalizing the Mushaf for the first time. Abu al-Aswad al-Du'ali is considered the first to vocalize the Mushaf individually, followed by Ibn Sirin, while Abd al-Malik was the first to officially order the vocalization of the Mushaf on a general scale.

As for what has been reported about Al-Hajjaj changing eleven letters in the Uthmanic Mushaf, it is a very weak or fabricated narration due to the presence of "Abbad ibn Suhayb," whose narrations are abandoned, and its content is false and reprehensible, making no sense. Major scholars, Muslim and non-Muslim alike, have denied it, affirming that the Quran cannot be altered.