Secure Multi-Party Computation (MPC) wallets enhance cryptocurrency security by distributing private key shards across multiple parties, eliminating single points of failure. However, vulnerabilities in key shard management can compromise this model. A notable case involved a major wallet provider in 2024, where researchers uncovered flaws in the Gennaro and Goldfeder MPC algorithm, requiring up to nine signature rounds, exposing shards to prolonged attacks. Another vulnerability surfaced in an MPC wallet with inadequate key rotation, allowing attackers to intercept shards before refresh. These cases highlight risks like phishing targeting shard holders and insufficient encryption, emphasizing the need for robust key refresh mechanisms and secure storage to prevent unauthorized access and ensure transaction integrity in MPC-based systems.