Web Vulnerabilities
Serialization
Also: marshalling
Turning a program's in-memory objects into bytes or text so they can be stored or sent.
In more detail
A shopping cart object can be written as bytes into a cookie or a file, then rebuilt later. Formats differ in power: JSON can only describe plain data, while formats such as Python pickle or Java native serialization can also describe which code to run while rebuilding. That difference decides whether loading is safe.