What are common causes of malformed JSON leading to this error?

Common causes of malformed JSON include missing commas between key-value pairs or objects, unescaped special characters within strings (like quotes), incorrect data types (e.g., using a string where a number is expected), and trailing commas at the end of objects or arrays. Also, ensure that the JSON structure adheres to the JSON specification (e.g., keys must be strings enclosed in double quotes).