Dorset DG 201 Digital Lock NFC Card Cloning Vulnerability

A vulnerability exists in the Dorset DG 201 Digital Lock model H5_433WBSK_v2.2_220605, allowing attackers to clone NFC cards and bypass authentication. This issue arises from how the lock stores NFC card data, which can be exploited to create duplicate cards that the lock cannot distinguish from the original.

Impact

Exploitation of this vulnerability allows for unauthorized access by cloning NFC cards that can bypass the lock's authentication system.

Reproduction

The vulnerability can be reproduced by using a Flipper Zero device, which can copy NFC credentials from a card or fob with less than a second of contact. The cloned information can then be written onto a blank card, effectively duplicating the original. This method takes advantage of the lock's use of Mifare Desfire EV1 2K NFC cards, which, despite being more secure than older standards, can still be compromised if the default sector passwords are not changed.