Apple provides a rich set of APIs to developers that is aiming to let them perform any task in a robust and secure way. The NS prefix commonly used in names in the past stands for NeXTSTEP—the platform they were originally designed for. The CF prefix is the abbreviation of the Core Foundation framework, which is a C API for macOS and iOS. The reason they co-exist and sometimes provide similar functionalities is mainly historical, as this is the result of merging the classic Mac OS toolbox and OPENSTEP specification. There is even a special term for using the corresponding logic interchangeably: toll-free bridging.
Here are some examples of classes commonly misused by malware:
- Filesystem operations: To begin with, various classes from the File System group of the Foundation framework can be used to perform file operations. Malware can use them for multiple purposes; for example, to relocate its own modules, store malicious configuration, or get access to sensitive data. Examples...