What is "kleptography"

n. The theft of information in a secure and unobtrusive manner

Kleptography is the study of stealing information securely and subliminally. Kleptography is a subfield of cryptovirology and is a natural extension of the theory of subliminal channels that was pioneered by Gus Simmons while at Sandia National Labs. Kleptography is also related to steganography. The concept of an asymmetric backdoor (synonymously referred to as Kleptography) was introduced by Adam Young and Moti Yung in the Proceedings of Advances in Cryptology—Crypto '96.