Is there anyone who transitioned from IT to mathematics?

I am obtaining my bachelor's degree in computer science (information security major) this year. I come from a mathematics olympiad/competitive programming background and I feel more comfortable in the theoretical world of mathematics and algorithms than in the world of industrial applications (I am more proficient in it, too).

Do you think it's a good idea to pivot at this point (perhaps pursue a Master's degree in mathematics)? Do you have any success/failure stories to share?