To pass the CBSE exams, a student must obtain a minimum of 33% of total marks. The passing marks out of 80 in CBSE exams are 26 marks (rounded off). Therefore, a student needs to score at least 26 marks out of 80 to pass the exam. It is important to note that meeting the passing criteria is mandatory for practicals, theory, and internal assessment in CBSE Class 12 and 10.