If you're sent a QR code for a ChastiKey lock, or one is published on the forums then please load them within the app and not with a 3rd party QR code scanner. ChastiKey QR codes are not encoded with a URL so loading them in a 3rd party QR code scanner will not take you to or load the lock.
If you scan a QR code in the ChastiKey app and that QR code happens to be encoded with a malicious or spam URL from a user pretending to share a ChastiKey lock then nothing would happen as it will just say that the lock doesn't exist. It won't try and load or redirect you to the URL that's encoded.