Canary trap

Common card · No. 204449

A canary trap or barium meal test is a method for exposing an information leak by giving different versions of a sensitive document to each of several suspects and seeing which version gets leaked. It could be one false statement, to see whether sensitive information gets out to other people as well. Special attention is paid to the quality of the prose of the unique language, in the hopes that the suspect will repeat it verbatim in the leak, thereby identifying the version of the document.

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