Overall, Dowd and Mandt concluded that Apple has mitigated many weaknesses with iOS6, which makes its kernel much harder to exploit.
"All the previous techniques that have been used have basically been made for the most part useless," Dowd said. "But there's still room to move and its still possible to exploit the kernel in iOS6, but the bar has definitely been raised."
But all are attracted to the challenge.
"It's very engrossing," Wang said. "It's kind of like doing a very complicated Sudoku or a crossword but it's like 10 times harder. It's just entertaining to be able to use your brain in that way. It's really the only reason I do it."
Cyril remained positive about the eventual outcome: "I'm still confident we can find something in the next few weeks."
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