Jailbreak detection: what can it do and where are its limits?
Essence
A jailbreak lifts the sandbox and code-signing restrictions: the device can run any code, inject libraries into other processes and hook function calls. For an app this means the device owner controls its process: they can read memory, change the results of checks and call internal methods. Jailbreak detection tries to notice such an environment, but it operates on the same ground as the attacker.
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