Can I separate a string using a a number as the starting point and a comma as the ending point?

So here’s an example string:
CN=John Doe,OU=IT,OU=Management Support Services,OU=Divisions,OU=Accounts,DC=company,DC=com

I only need to get the first name out of this string. In this case the name being John Doe. I can’t hard code a number of characters in as the names there can vary in length.

Basically I need to select the string after CN= and then end it at the first comma.

The first number can always be 3 characters since the CN= is always there. Is there anyway for me to use the first comma as the end point?

I’m trying to do something like this.

let name = reports[i].mgrdn;
let result = name.split(3, “,”)

Any help would be appreciated. Even just a suggestion about what method to use.