The new jailbreak for iOS 6.1, named Evasi0n, is detailed in this article, thanks to Braden Thomas. A few more details are needed regarding the very end on the page signing cancelation. Actually, in order to evade code signed verification, the amfi.dylib is cleverly structured. The idea is as follow: force the MISValidateSignature (which returns the status of code signing verification) to always return 0. That way, one will be able to execute any unsigned code. Hence, this raises 2 questions: How to force MISValidateSignature to always return 0? How to pass the code signed verification for amfy.dylib?
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