Unlooper

An unlooper is a smart card repair device intended to break the card's microcontroller out of an infinite loop that has been either accidentally or intentionally programmed into the card's internal memory.

A looped smart card is generally unusable, and may be permanently rendered nonfunctional (bricked) unless an unlooper is able to get the microcontroller out of the infinite loop.

An unlooper is a tool that has both legal and illegal purposes, for use by smart card software developers to recover from programming mistakes, and by those attempting to hack smart card security systems.