Sahih Muslim 1465
صحيح مسلم#1465SahihAbu Dharr reported:The Messenger of Allah (ﷺ) said to me: How would you act when you are under the rulers who would delay the prayer beyond its prescribed time, or they would make prayer a dead thing as far as its proper time is concerned? I said: What do you command? He (the Holy Prophet) said: Observe the prayer at Its proper time, and if you can say it along with them do so, for it would be a superetogatory prayer for you. Khalaf (one of the narrators in the above hadith) has not mentioned" beyond their (prescribed) time
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 5:298