Easy to program own secrets
The YubiKey requires no special hardware for programming, enabling you to easily program and control your own encryption keys. If required, Yubico offer optional password write protection of the settings, but all YubiKeys sold on our web store can be re-programmed. For security reasons Yubico firmware is not upgradable, it’s a write only device and the encryption key can never be read out from the device.
Tamper proof casing
The YubiKey is based on standard components, high-pressure moulded into plastic, making it practically impossible to tamper. If tampered, it will require sophisticated equipment to read out the secrets and cannot be done without physically destroying the device. Each YubiKey is seeded individually, so any breach would be for that unique Yubikey only, there is no systemic breach. If lost or stolen, the user administrator can easily disable the YubiKey so that it no longer can be used.
I'm sorry, but do you have an unencrypted backup ? It's impossible to read the keys out especially when you've overwritten it.
How much damage was caused?
