Question
Is it permissible to pray without reciting Attahiyyat (Tashahhud)?

Answer
No, you cannot pray without reciting Attahiyyat, as it is Wājib in Salāh.

If a Wājib is missed unintentionally (by mistake):
You can rectify the Salāh by performing Sajdah-e-Sahw (prostration of forgetfulness) before concluding the prayer.

If a Wājib is missed intentionally (on purpose):
The Salāh becomes makruh-e-tahrimi and must be repeated (Wājib-ul-I’ādah).

While praying behind an Imām (congregational prayer):
If you miss a Wājib unintentionally, there is no need to perform Sajdah-e-Sahw, as the Imām's prayer covers such mistakes.
However, if you miss a Wājib intentionally, the prayer becomes makruh-e-tahrimi, and you must repeat it.

And Allah knows best.

Muhammad Rehan Raza Qadri
(Beggar at the doorstep of Scholars)