Short answer
None that all Jains accept. The two great Jain traditions, the Svetambaras and the Digambaras, do not share the books that record Mahavira's words. He was the last of the Jain Tirthankaras (teachers). The Digambaras do not admit that the Svetambara Angas survive in authentic form. Both traditions say that the oldest teaching, the fourteen Purvas, was lost. The Digambaras say that the main books, the Angas, were lost too. The two even tell Mahavira's life differently. A Svetambara scripture names his wife, Yasoda. The Digambaras hold that he never married. So no one book, accepted by all Jains, stands as the Jina's word. The Qur'an makes a claim that anyone can check. God (﷾) says He will guard it, and every Muslim community today holds the same book of 114 surahs (chapters).
Full explanation
What both traditions say was lost
Hermann Jacobi translated central Svetambara texts in 1884 and 1895. He reports a point on which both traditions agree. Besides the Angas, the main books, there were once fourteen older works, the Purvas. Knowledge of them faded until it was extinct. Jacobi saw no reason to doubt this old tradition. He adds that the Digambaras have lost the Angas as well.
“we are told by the Svetambaras, as well as the Digambaras, that besides the Angas, there existed other and probably older works, called Purvas, of which there were originally fourteen. The knowledge of these Purvas was gradually lost, till at last it became totally extinct.”
“the Digambaras also have lost the Purvas, and the Angas to boot”
Where the two traditions stand
The Jain scholar Padmanabh Jaini sets out where the two main Jain groups stand. The Svetambaras (the white-clad) accept forty-five texts that survive as their scripture. The Digambaras (the sky-clad) keep the names of the oldest texts, the Purvas and the Angas. But they do not accept that any of them survives in its true form. Instead they hold two early works, the Shatkhandagama and the Kasayaprabhrta. These come from a few parts of the lost teaching on how karma binds the soul. So the Digambaras do not accept the Svetambaras' Angas as the real thing.
Jaini writes that the Svetambaras accept forty-five extant texts as canonical, though the Sthanakavasi, a Svetambara sect, accept a shorter list (p. 49, n. 12). The Digambaras keep the names of the Purva and Anga texts but do not admit that any of them survive in authentic form (p. 49, n. 12). In the Digambara account, a few sections on karma theory from the lost twelfth Anga were passed down by the teacher Dharasena to Pushpadanta and Bhutabali, who wrote them down as the Shatkhandagama, and another Digambara teacher drew on the same source for the Kasayaprabhrta; these are the only canonical works the Digambaras possess (pp. 50-51). Jaini adds that they have consistently maintained that the Anga texts were "totally lost" as early as the second century CE, and that the Svetambaras preserved large portions of the Anga texts though they lost the Purvas and the twelfth Anga (p. 51).
Two accounts of Mahavira's life
The two groups also tell Mahavira's life differently. The Acaranga, a Svetambara scripture, names Mahavira's wife, Yasoda. The Digambaras believe he never married. They also differ over a story of his birth, in which his embryo was moved from one womb to another. The Svetambaras accept the story, and the Digambaras reject it. And they differ over clothing. The Digambaras hold that Mahavira and every true monk went without clothes. The Svetambaras do not require it. Jaini calls this the main point they disagree on.
“His wife Yasodâ belonged to the Kaundinya gotra.”
Jaini reports that the Svetambaras hold that Mahavira married the princess Yasoda and fathered a daughter, while the Digambaras believe he remained a bachelor throughout his life (p. 11). On clothing, he writes that the Digambaras believe Mahavira and the other Jinas went without clothing at all times after their renunciation, and that every Jain monk must do the same. In the Svetambara account Mahavira wore a cloth for a time before going without clothing, and the Svetambaras do not require their monks to go without clothing. Jaini calls this doubtless the single most important point of contention between the two traditions (p. 13).
In a note on Mahavira's family, Jacobi records that the story of the transfer of Mahavira's embryo from the womb of the Brahmin woman Devananda to that of the Kshatriya woman Trisala is rejected by the Digambaras, while the Svetambaras uphold its truth. He adds that the story is found in the Acaranga, the Kalpa Sutra and many other books.
What the two traditions share
The two traditions are close in doctrine. Jacobi says their philosophy is nearly the same, though their ethics differ more. Both accept one text as authoritative, the Tattvartha Sutra of Umasvati. Even there, their versions differ on matters such as the nudity of the monk, and each has its own commentaries. A shared summary of the teaching is real. It is not a shared record of the Jina's own words.
“after the splitting of the church in these two sects the philosophical system of the Gainas remained stationary, since it is nearly the same with both sects. As regards ethics, both sects, it is true, differ more.”
Jaini writes that the Tattvartha Sutra of Umasvati, a summary of Jain doctrine in 350 sutras (short aphorisms), is the one text recognised as authoritative by Digambaras and Svetambaras alike. Both traditions claim Umasvati as their own, but their versions of his work disagree on matters such as the nudity of the monk and the eating of food by the kevalin (the omniscient one). Each tradition has its own commentaries, which present almost identical accounts of the doctrine. The Digambaras dispute the authenticity of the Svetambara self-commentary on the work (p. 82).
Islam's answer: one Book
Islam makes a claim that anyone can check. The Qur'an says that God (﷾) sent it down and will guard it, and that falsehood cannot come near it. Muslim communities today all hold the same book of 114 surahs. None has a rival Qur'an to set beside it. Sahih al-Bukhari reports that Gabriel went over the Qur'an with the Prophet (ﷺ) every year, and twice in his last year. A Jain who asks where the Jina's word can be found, whole and agreed on, is invited to read the Qur'an. He or she is also invited to learn about the last Prophet (ﷺ), to whom it was revealed.
“We have, without doubt, sent down the Message; and We will assuredly guard it (from corruption).”
“No falsehood can approach it from before or behind it: It is sent down by One Full of Wisdom, Worthy of all Praise.”
Abu Hurayra reports that Gabriel went over the Qur'an with the Prophet (ﷺ) once every year, and twice in the year he died.
The replies, answered
Qur'an 15:9 — Surat al-Hijr (The Rock), verse 9
“We have, without doubt, sent down the Message; and We will assuredly guard it (from corruption).”
Cited for
Muslim scholars disagree too. There are four schools of law, and they differ on many rulings.
The response
They do differ, and the schools say so openly. But they differ over what to conclude from one Book that all of them accept. The Jain disagreement is over which books exist, and which of them carry the Jina's teaching. No school of Islamic law has a Qur'an of its own.
Where it lands — A disagreement over rulings drawn from one agreed text is not a disagreement over what the text is.
Jacobi, Gaina Sutras part I (SBE 22, 1884), Introduction, p. xlvi
“after the splitting of the church in these two sects the philosophical system of the Gainas remained stationary, since it is nearly the same with both sects. As regards ethics, both sects, it is true, differ more.”
Cited for
The core is shared. Both traditions teach non-violence and karma, and both accept the Tattvartha Sutra.
The response
Granted, and Jacobi says the same of their philosophy. The question here is not whether the two traditions are alike. It is whether one record of the Jina's own words stands behind them both. The Tattvartha Sutra is Umasvati's summary, and the two traditions' versions of it differ.
Where it lands — Shared teaching is real, but it does not give the two traditions one agreed record of Mahavira's words.
Hermann Jacobi, Introduction to the Gaina Sutras, part I (Sacred Books of the East 22), 1884, p. xliv — the Purvas
“we are told by the Svetambaras, as well as the Digambaras, that besides the Angas, there existed other and probably older works, called Purvas, of which there were originally fourteen. The knowledge of these Purvas was gradually lost, till at last it became totally extinct.”
Cited for
The Svetambara canon is old, and Jacobi himself judged the Angas ancient.
The response
Jacobi did judge the Angas old, and this page does not dispute it. Old and agreed are different things. The Digambaras, who are also Jains, do not admit that the Svetambara Angas survive in authentic form. On the same page, Jacobi reports that the older teaching, the Purvas, was lost.
Where it lands — Age does not settle the question. A canon that the Digambaras do not accept cannot be the one book all Jains hold.
Acaranga Sutra 2.15.15 — book 2, lecture 15, §15
“His wife Yasodâ belonged to the Kaundinya gotra.”
Cited for
These are small details of Mahavira's life. They do not touch the teaching.
The response
Whether the details are large is not the point. Two groups of followers hold different accounts of the same man, each from its own books. Neither can appeal to a book that the other accepts. A Muslim of any community can appeal to the same Book.
Where it lands — The difference shows that there is no single Jain record to appeal to.
Dundas, The Jains (2002), chapter 6
Dundas writes that, by around the early common era, Jains recognised that a variety of advanced spiritual attainments, of which enlightenment (full omniscience) was one, were no longer possible in this era after the death of the disciple Jambu. Religious practice then aimed not only at burning away karma but also, increasingly, at gaining merit for a good rebirth (chapter 6, opening page, p. 94).
Cited for
Jainism needs no revealed book. The soul reaches omniscience by its own effort, and scripture only points the way.
The response
Dundas reports that Jains came to hold that, in this era, after the disciple Jambu, omniscience can no longer be reached. So Jains today depend on the teaching handed down, and that is what the two traditions dispute. The Qur'an claims to be guidance sent down by One Full of Wisdom (41:42), which God (﷾) Himself guards (15:9). Every Muslim community today holds the same text.
Where it lands — If no one in this era reaches omniscience, a Jain needs a trusted record of the teaching. The two traditions have no single one.
Qur'an 41:42 — Surat Fussilat (Explained in Detail), verse 42
“No falsehood can approach it from before or behind it: It is sent down by One Full of Wisdom, Worthy of all Praise.”
Cited for
Muslims also keep many hadith collections, and not every Muslim accepts the same ones.
The response
This page is about the Book each tradition says is God's (﷾) word. Reports of the Prophet's (ﷺ) words and deeds are a separate matter, and scholars grade them one by one. The Qur'an itself is the same book everywhere.
Where it lands — Differences over graded reports do not touch the question of which book is God's (﷾) word.
Perspectives
The Svetambara scriptures
The Svetambaras hold that their scriptures, the Agamas, carry down Mahavira's teaching. These are the Angas and other texts. Only the Purvas and the twelfth Anga were lost. They hold that Mahavira married, and that the story of his embryo being moved is true.
The Svetambara tradition (the white-clad)
The Svetambara scriptures hold what survives of Mahavira's teaching: the Angas and other texts. Only the Purvas and the twelfth Anga were lost.
Rebuttal
Grant that the Svetambaras kept large portions of the Angas. The Digambaras, who are also Jains, do not admit that these texts survive in authentic form.
The Svetambara scriptures record Mahavira's life, including his wife, Yasoda, and his daughter.
Rebuttal
Grant that the Acaranga says so plainly. The Digambaras hold that Mahavira never married. Two accounts of one life cannot both be true, and no book that both traditions accept settles it.
The Digambara scriptures
The Digambaras hold that the Angas and the Purvas were lost. Only parts of the lost teaching live on, in two early works. They do not accept the Svetambara books as genuine.
The Digambara tradition (the sky-clad)
Parts of the lost teaching live on in two works, the Shatkhandagama and the Kasayaprabhrta. They were passed down from the teacher Dharasena.
Rebuttal
Grant that these are early and real works. Both deal with how karma binds the soul. For the rest of the Jina's teaching the Digambaras hold the canon lost.
Mahavira never married, and after leaving home he lived without clothing, as every true monk must.
Rebuttal
Grant that this is the Digambara account. The Svetambara scripture says otherwise about his wife. No Jain book that both traditions accept settles it.
The core teaching is shared
Whatever the two traditions say about books and monks, they teach nearly the same philosophy. Both accept the Tattvartha Sutra, so the Jina's teaching is not in doubt.
Jains who point to what the two traditions hold in common
The two traditions teach nearly the same philosophy, and both accept the Tattvartha Sutra.
Rebuttal
Grant it; Jacobi says so too. But the Tattvartha Sutra is Umasvati's summary, and the two versions differ on the monk's nudity. A shared summary is not a shared record of the Jina's words.
The disputes are about monks' practice, not about the teaching.
Rebuttal
Grant that the philosophy is nearly the same. The disputes also cover which books are authentic, so the two cannot settle them from one shared text. Jaini calls clothing the chief point of contention.
What the record shows
Both Jain groups say the Purvas were lost. The Digambaras do not accept that the Svetambara Angas survive in their true form. The two groups tell Mahavira's life differently. And the one text both accept is a teacher's summary.
Both the Svetambaras and the Digambaras speak of the fourteen Purvas, the oldest teaching. They say these were lost bit by bit until none was left.
The Digambaras do not accept that the Svetambara Angas survive in their true form. They hold that the Angas were lost.
A Svetambara scripture names Mahavira's wife, Yasoda, while the Digambaras hold that he never married.
The Svetambaras uphold the story of the transfer of Mahavira's embryo, and the Digambaras reject it.
The one text both groups accept is the Tattvartha Sutra of Umasvati. And their versions of it differ.
The Islamic perspective
The test is a plain one: is there one book that every community of its followers holds as the word of God (﷾)? The Qur'an passes it. God (﷾) promises to guard it, and every Muslim community today holds the same book of 114 surahs. A reader is invited to examine the Qur'an and the life of the last Prophet (ﷺ).
The Qur'an says God (﷾) sent it down and will guard it.
The Qur'an says that falsehood cannot approach it from before or behind.
Gabriel went over the Qur'an with the Prophet (ﷺ) every year, and twice in his last year.
Every Muslim community today holds the same Qur'an of 114 surahs. So all Muslims have one book to turn to.