Back doors are doors at the rear of a building, often used for service or quiet entry. The phrase can also mean a hidden or unofficial way into a system or deal, bypassing rules.
Free open-source software, by its nature, is unlikely to feature secret back doors that lead directly to Langley, Va. Evgeny Morozov
The director of the FBI has been visiting Silicon Valley companies asking them to build back doors so that it can spy on what is being said online. The Department of Commerce is going after piracy. At home, the American government wants anything but Internet freedom. Evgeny Morozov