Convert a string with commas to a multidimensional object javascript

I have a big JSON file with “key:value” format like this:

{
    "str1,str2,str3,str4,title": "VALUE OS THIS KEY",
    "str1,str2,str3,str4,description": "VALUE OS THIS KEY",
    "str1,str2,str3,str4,value": "VALUE OS THIS KEY",
    ...
    "str1,str2,str3,str5,title": "VALUE OS THIS KEY",
    "str1,str2,str3,str5,description": "VALUE OS THIS KEY",
    ...
    "str1,str_other,str3,str4,title": "VALUE OS THIS KEY",
    ...
}

And I want to transform this keys into an object to make a new JSON and work with it like this:

{
  str1:{
    str2:{
      str3:{
        str4:{
          title: "VALUE OS THIS KEY",
          description: "VALUE OS THIS KEY",
          value: "VALUE OS THIS KEY"
        },
        str5:{
          title: "VALUE OS THIS KEY",
          description: "VALUE OS THIS KEY"
        }
      }
    },
    str_other: {
      str3:{
        str4:{
          title: "VALUE OS THIS KEY"
        }
      }
    }
  }
}

I try it with javascript forEach but I don’t know how to create this multidimensional array.
Can anyone show me how to do that?

Thank you very much in advance