Suppose there's a vault secured with a numeric code and a biometric sensor. What technologies and methods could be used to open the vault if a character isn't registered on the system?
Here are a few biometric systems I'd be interested in seeing solutions to bypassing and some ideas I have already considered, though don't know if they're viable.
Finger-/handprint sensor -- A device that reads one or more fingerprints or the entire hand, requiring a 97% or better match to unlock.
Cut off the hand of a valid user (seems rather violent and not feasible for a burglar)
Place a sheet of material (graphene?) on the sensor thin enough to not be noticed and thick enough to record the finger-/handprint of a valid user
Genetic sensor -- A device that retrieves a fresh sample of DNA from a user, requiring a 97% or better match to unlock
- Retrieve a sample of a valid user's DNA from a third party (Red Cross looking for blood donors!) and construct a fake hand from pig flesh
Iris sensor -- A device that examines a user's eye, requiring a 97% or better match to unlock
Rip the eye out of a valid user's head (again, infeasible for a burglar)
Construct a device that mimics the pattern of a valid user's eye (though I don't know how to go about getting the pattern)
Face sensor -- A device that performs facial recognition, requiring a 97% or better match to unlock
- Use a 3D printer to create a foam replica from pictures of a valid user
These are just some of the biometric sensors I can think of. Answers to this question should be limited to bypassing the biometric portion of the vault security without resorting to drills and other vault penetration tools (or removing the power source) and should result in a minimum of proof of a burglar's presence. If there are other biometric systems you can think of, feel free to share them and a possible way to bypass them.