South Korea’s financial regulators have ordered all domestic crypto exchanges to adopt a single, strict system for delaying withdrawals, aiming to block a surge in voice phishing scams that rely on speed.

The Financial Services Commission and Financial Supervisory Service announced the new rules, removing the discretion exchanges once had to let users bypass holding periods, local news outlets report.

In the past, platforms set their own exceptions to keep trading fast. Fraud groups learned those rules and coached victims to slip through them.

Voice phishing scams often push victims to convert cash into crypto and send it out within minutes. A delay, even a short one, can interrupt the scam by giving victims time to reconsider or allow…