What if someone scans your passport into their ZKPassport App?
This is more of a question than a request. I am building a (experimental) voting platform and currently thinking through attack vectors. In this case, what if an individual is able to access your passport temporarily; long enough to scan it into their ZKPassport App, after which point they lose access to the physical passport. Would the passport owner have any recourse to invalidate the attacker’s scan (presumably by re-scanning it themselves?)? If not … do scanned passports expire in the app (requiring re-scanning) so that the attacker’s version becomes invalid after a certain period (hopefully less than expiration date of the passport)? If not, is there anything that can be done at the application level, such as detecting that proof A uses a passport more recently scanned than proof B?
Thanks for the consideration!
Comments1
Niall Cheetham
Dec 1, 2025
Hi Mitchell,
1. Do scanned passports expire in the app
- No they do not, however this is good feedback we will discuss internally!
2. Anything that can be done at the application level.
- To solve this we introduced private face match. You can see an example of it here. https://demo.zkpassport.id/?fm=2. The documentation can be found here. https://docs.zkpassport.id/examples/facematch. If your passport is stolen they will be unable to generate a facematch proof.
We do also have ideas around, but still in the exploration phase to restrict the number of proofs that a device can generate.
In regards to the last paragraph, this is something that we have not discussed !