var str='var data = {"value":"abc","value2":"def","value3":"ghi"};';

var start=str.indexOf('{');
var end=str.indexOf('}');
var str=str.substring(start,end+1)

gs.info(str)

var data=JSON.parse(str); // Now you will have a valid JSON String

//Now access them as below

gs.info(data.value);// Now data.value1 will hold "abc";
gs.info(data.value2);// Now data.value2 will hold "def";
gs.info(data.value3);// Now data.value2 will hold "ghi";

Please mark it as helpful/correct If my answer is helpful in any way,

Best regards,

Thameem

I fixed the issue in my previous code

please try the above code. its tested