Yes you can shift your career from networking to cyber security engineer.
Here are some steps one can take:
Look up the abilities you have developed at your current employment that you can use to your future position.
Find out what skills you need to start learning for your new work by doing some research.
Establish contact with experts in your new field of work.
Don't forget to update your resume to reflect your new career.
Although changing careers can be difficult, it is possible with the proper planning and preparation. For that I would like you to suggest this linux certification course offered by Intellipaat. This program is specially designed for both freshers and experienced so that anyone can learn it easily. This program helps you to gain better insights of Linux which is important subject of cyber security.
Before enrolling have a look at this video on how Janardan switch his career from network to cyber security engineer with the help of Intellipaat -