Security researcher Baptiste Boileau from the Ledger Donjon division has discovered a critical physical vulnerability in Tangem hardware wallets. The method, based on laser fault injection, allows resetting the card's password and gaining full control over the crypto assets stored on it. This concerns wallets in the form of NFC cards that externally resemble bank cards but contain a secure chip for storing private keys and signing transactions.
According to data obtained during the research, the vulnerability affects all Tangem models currently in circulation. The key issue is the impossibility of fixing it via a patch, as the devices do not support firmware updates. This makes the attack particularly dangerous for lost or stolen cards.
Attack Details
Inside the Tangem wallet, a Samsung S3D232A secure element with EAL6+ certification is installed. Typically, access to funds is protected by two factors: physical possession of the card and knowledge of the password. However, Boileau identified a weakness in the logic of the SetPin instruction used when changing the password. The firmware includes a check that allows recovery only when two linked cards are present. Laser fault injection bypasses this check, forcing the chip to accept a new password without the old one or a backup card.
To execute the attack, the researcher opened the card, exposed the secure element, connected it to his own hardware platform, and used side-channel analysis to determine the exact moment of the check execution. He then directed a nanosecond laser pulse at a specific area of the chip. After resetting the password, the attacker gains the ability to sign transactions and withdraw funds. Each successful attempt is estimated to require about two hours of preparation and exploitation.
Threat Realism
The attack requires not only physical access to the card but also expensive equipment — the laboratory setup is estimated to cost approximately $250,000. In addition to the laser tool, skills in hardware security and side-channel analysis are necessary. Tangem noted that the risk for ordinary users is "practically non-existent," emphasizing that Ledger Donjon is a division of their direct competitor. Nevertheless, Boileau pointed out the limitations of EAL6+ certification: it confirms the chip's resilience according to certain criteria but does not guarantee the absence of vulnerabilities in the firmware logic.
Expert Conclusion
This case demonstrates a fundamental problem: even certified secure elements are not protected from errors in the software code running on top of them. For the industry, this is a signal: hardware wallet developers must implement multi-layered protection, including independent checks for critical operations and robust state encoding. Users should remember that the physical security of the device is only part of the equation; a lost card can become an entry point for professionals with access to laboratory equipment.