Master Keying Vulnerabilities Disclosed: New York Times 2003

A 2003 article by the New York Times examined the security vulnerabilities of master key systems, especially in apartment complexes. Matt Blaze first reported on the issue, and Marc Tobias was also quoted in the article.

In the research paper, Mr. Blaze applies the principles of cryptanalysis, ordinarily used to break secret codes, to the analysis of mechanical lock designs. He describes a logical, deductive approach to learning the shape of a master key by building on clues provided by the key in hand — an approach that cryptanalysts call an oracle attack. The technique narrows the number of tries that would be necessary to discover a master-key configuration to only
dozens of attempts, not the thousands of blind tries that would otherwise be necessary.

Many Locks All Too Easy To Get Past – The New York Times