Insecure deserialization in Node.js can expose sensitive data and allow attackers to manipulate serialized objects, leading to arbitrary code execution (ACE) vulnerabilities. The `node-serialize` package is vulnerable to insecure deserialization due to its ability to serialize functions, making it susceptible to prototype pollution attacks. By using the `serialize-javascript` package, which sanitizes user inputs before serialization, developers can prevent these types of attacks. Additionally, avoiding deserialization of user inputs altogether is the best way to protect against insecure deserialization vulnerabilities. The Snyk Code extension can help identify potential security issues in code and recommend fixes, including the use of `serialize-javascript` to secure deserialization processes.