Yishi: iPhone 11 and earlier models have a hardware vulnerability; storing mnemonic phrases is not recommended.

OnKey founder Yishi stated that iPhone 4S to iPhone 11 series models contain a BootROM hardware vulnerability that cannot be fixed through iOS system updates. Attackers, after gaining physical access, can execute code via the USB interface. Yishi advises users not to use iPhone 11 and earlier models to store mnemonic phrases, and users already using such devices should generate new mnemonic phrases in a trusted environment and migrate their assets.