ATMs Go Down in Japan, $133 Million Vanishes From a French Bank, and Brazil's Biggest Crypto Apps Freeze Transfers

Within the span of five days, customers in three different countries found themselves locked out of their money or their crypto, for three different reasons. None of the incidents are confirmed to be connected, but together they paint a picture of how fragile the plumbing behind both traditional banking and crypto on-ramps has become.

JAPAN'S ATMS GO DARK

A system failure at Shinkin Central Bank disrupted customer transactions at 128 shinkin banks across western Japan on November 6, suspending ATM services, branch counter transactions and internet banking, with the outage beginning around 1:30pm and affecting 3,430 branches. Equipment malfunction is believed to be the cause, and the possibility of a cyberattack has been ruled out for now.

The Shinkin Joint System is used by 236 shinkin banks, more than 90% of all shinkin banks nationwide. This time, the failure occurred only at the western Japan center of the two centers split between east and west. The system was fully restored shortly after 7pm the same day, according to Shinkin Central Bank, the Shinkin Kyodo Center and the National Association of Shinkin Banks.

A FRENCH BANK'S $133 MILLION PROBLEM

Two days earlier, a very different kind of failure hit a French lender. Crédit Mutuel Arkéa said attackers were able to make transfers using the bank's own account after compromising an unnamed supplier, with the statement stressing customer accounts were not accessed. Details were first reported by ZachXBT, a pseudonymous blockchain investigator, who said the attack had run over several days and estimated the theft at more than $133 million.

About $63 million in stablecoins was swapped for 27,553 Ether during the night of November 1 to 2, using decentralized protocols including Uniswap, with subsequent transfers passing through instant-swap services and the privacy coin Monero. The bank, which manages nearly $238 billion in assets and serves over 5.8 million members, assured the public that depositors will not bear financial losses from the attack.

BRAZIL'S CRYPTO GATEWAYS FREEZE

Brazil had its own rough week, with trouble starting at the country's largest crypto exchange. Mercado Bitcoin, described as Brazil's largest crypto exchange, said it had identified and contained a security incident in one of its systems in the early hours of November 2, suspending deposits and withdrawals and taking its app offline, with the exchange absorbing a loss on the incident. Mercado Bitcoin plans to reopen its website on Monday, November 9, but only to check balances and statements, with withdrawals, transfers, trading and deposits remaining suspended.

Four days later, two of the region's biggest consumer fintechs hit a separate snag. Nu Holdings, which runs Nubank, temporarily suspended cryptocurrency deposits and withdrawals in Brazil because of a problem with an external provider, a week after hackers stole $6.3 billion from Binance Holdings. Nubank and Mercado Pago halted key cryptocurrency transfer functions on Friday, November 6, following technical issues at their external screening providers, with the disruption specifically affecting crypto deposits and transfers between external wallets, though customers could still buy and sell digital assets within each app.

The pause came in the same week that Chainalysis, the blockchain analytics firm Nubank uses to screen crypto transfers, disclosed that attackers had accessed the credentials of every user on its platform. Exame reported that Nubank's direct transfer feature runs on its partnership with Chainalysis, and Chainalysis said names, usernames, password hashes and live tokens for all of its users had been exposed to a malicious actor. Nubank has not named the supplier behind Friday's disruption, and neither company has publicly linked the two events.

THE COMMON THREAD

Three incidents, three causes: a hardware failure at a shared cooperative-banking data center, a cyberattack that routed stolen money through crypto exchanges, and a compliance vendor outage that froze legitimate transfers as a precaution. None of them required a single point of attack to cause widespread disruption. Shared infrastructure, whether it's a joint banking network, a payment processor's supplier, or a transaction-screening vendor, means one failure can ripple across millions of accounts at once. For anyone holding Bitcoin outside of these systems, the week offered a quiet reminder of why self-custody exists in the first place.

This story comes from the Simply Bitcoin Live show. Watch the full episode.