XKEYCHAINX LABS
Tangem / Public disclosure

Access-code retry-delay bypass

Donjon reports faster access-code guesses through a tearing attack.

Source date: 2025-09-17Reviewed: 11 October 2026

Affected scope

Tangem card authentication

What the attack requires

Physical card access; weak access code materially increases exposure.

Response & remediation

What changed

No field firmware update for existing cards per researcher.

What this finding establishes

The researcher’s account includes the vendor’s disagreement over practical severity. This is distinct from the 2026 laser password-reset finding.