Multiple banks in Eastern Europe have been attacked from inside their network via various electronic devices connected directly to the company’s own infrastructure. The losses created this way are estimated to tens of millions of dollars. The attacks targeted at least eight banks using readily-available gear such as netbooks or inexpensive laptops, Raspberry Pi mini-computers, or a Bash Bunny – a USB-sized piece hardware for penetration testing purposes that can pose as a keyboard, flash storage, network adapter, or as any serial device.
Source: https://www.bleepingcomputer.com/news/security/netbooks-rpis-and-bash-bunny-gear-attacking-banks-from-the-inside/