There's no specific syllabus for CAT, one needs to rely on past years sample papers to get a fair idea about the pattern and weightage given to each topic and section.In general, questions are mostly from middle school level English and Mathematics.
There are mainly three sections in CAT-
Logical Reasoning & Data Interpretation which includes topics such as Tables, Graphs, Data Caselets, Seating Arrangement, Blood Relation, Syllogism etc.
Quantitative Aptitude which includes topics such as Geometry, Algebra, Time and Work, Mensuration, Number System etc.
Verbal Ability & Reading Comprehension which includes topics such as Sentence completion, Questions based on reading comprehension, Para-jumbles & para-summar, inferences etc.
To know the detailed topics, kindly go through the following link-
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