The core text is the Old Testament with the axiom that the Old Testament needs rigorous analysis to understand how to apply it in real life. And that rigorous analysis is the Talmud. There is no claim that the Talmud is infallible. Every page and every word rises, stands or falls according to how logically rigorous they are. There is a claim that it partakes of the holiness of the Torah itself, but only in so far as it corresponds to some abstract objective measure of what the Torah actually means.
That is: it is text based. But there is an axiom that morality is objective and absolute and politically incorrect and not dependent on human perception or ideas. The Torah is given to us in order to help us perceive objective morality.
I am not saying yeshivas even the top and best ones are perfect. In a world where perfection is sadly lacking, they also subject to human flaws. But you have to keep your eyes on the goal post--to come to objective morality. When my father was teaching me how to sail, one thing I still remember he said. "Always keep your aim directed to one single point." [That is point the ship at one point on the shore. Or if you are on the open ocean then one point on the compass.]
How else are we to come to objective morality except by learning Torah? Gemara and Musar [the ethics of Torah]. And avoiding the cults.