Ledger, a hardware wallet provider, has identified security vulnerabilities in the microcontrollers of Trezor's Safe 3 and Safe 5 wallet models through its open-source research division, Donjon. These vulnerabilities could potentially allow hackers to bypass security checks using voltage glitching techniques. Trezor has acknowledged the issue and quickly patched the vulnerabilities in its older Safe 3 wallets. However, Ledger's Donjon team reports that despite these security improvements, a potential firmware bypass remains, leaving critical cryptographic operations exposed to risks. The affected Trezor wallets, despite their EAL6+ certification, continue to face scrutiny over their security architecture.