The write up can be found in the blog of the RedyOps Labs:
https://labs.redyops.com/index.php/2020/04/24/bitdefender-antivirus-free-escalation-of-privileges/
This exploit code, is heavily based on symboliclink-testing-tools which was Developed by James Forshaw. The symboliclink-testing-tools can be found here:
https://github.com/googleprojectzero/symboliclink-testing-tools