Turning an old iPhone into a hardware-like cold wallet is feasible, but not every model is suitable for secure storage.

Known vulnerabilities and affected models

The founder of OneKey warned that iPhone 11, iPhone XS, iPhone XR, iPhone SE 2020 and older models contain vulnerabilities that cannot be fixed with an iOS update.

According to the warning, a factory reset will not remove the exploitable condition, so restoring default settings does not guarantee security.

How the attack works and limitations of basic precautions

Exploitation requires physical access to the device, which means disabling network connections like airplane mode does not stop the threat.

Because an attacker needs direct contact with the phone, remote isolation measures alone are insufficient to prevent extraction of secrets.

Recommended devices and practical guidance

Devices beginning with iPhone 13 are reported to be unaffected by the two specific vulnerabilities, and so are recommended for cold-wallet conversions.

When choosing a phone for offline key storage, prioritize a model with confirmed mitigation against physical-exploit vectors and up-to-date firmware.

Demonstration and remaining risks

The published video guide demonstrates the entire process: from preparing the device to making the first transaction using QR codes and a companion app.

The tutorial also outlines residual risks that persist even after correct configuration, including risks tied to supply chain integrity and prior compromise of the device.

Readers considering reuse of consumer phones for cold wallets should verify device model and threat profile before moving funds to offline storage.