Exploiting Type Confusion Vulnerabilities in Oracle JRE (CVE-2011-3521/CVE-2012-0507) by Michael’mihi’ Schierl, @mihi42. This article is about so-called “Type Confusionvulnerabilities” in the Java Virtual Machine. A type confusion is a way to bypass the Java static type system by shadowing the corresponding private fields with public fields. Shadowing types is the most obvious way of exploiting type confusion to get code execution.”]
Source: http://schierlm.users.sourceforge.net/TypeConfusion.html