YubiKeys are vulnerable to cloning attacks thanks to newly discovered side channel
Sophisticated attack breaks security assurances of the most popular FIDO key. The YubiKey 5, the most widely used hardware token for two-factor authentication based on the FIDO standard, contains a cryptographic flaw that makes the finger-size device vulnerable to cloning when an attacker gains temporary physical access to it, researchers said Tuesday. The cryptographic flaw, known as a side channel, resides in a small microcontroller used in a large number of other authentication devices, including smartcards used in banking, electronic passports, and the accessing of secure areas. While the researchers have confirmed all YubiKey 5 series models can be cloned, they haven’t tested other devices using the microcontroller, such as the SLE78 made by Infineon and successor microcontrollers known as the Infineon Optiga Trust M and the Infineon Optiga TPM. The researchers suspect that any device using any of these three microcontrollers and the Infineon cryptographic library contains the same vulnerability.