Coincheck stated via its X account that the challenge was initially spotted at 3:09 am
The exchange canceled fresh and pending withdrawal requests. A few applications will be reviewed immediately once the systems are back up, while canceled funds will be returned to users’ account balances. Incoming transfers are still delayed.
Coincheck made it clear that the outage was to the fault of its service provider. The notice, written in Japanese, translates into English as: “This issue was caused by a failure in an external service we use, and there has been no unauthorized access or incident affecting our customers’ assets.”
What this implies is that there were no hacks or unauthorized access to customer assets, as deposits remain safe.
An external on-chain analysis tool at the center
Coincheck offered no details about the third-party service provider but said it was an external on-chain analysis service that it uses to screen crypto receipts and transfers.
Chainalysis offers that service to exchanges through its Know Your Transaction (KYT) product. KYT is used to observe crypto movements for illicit activity.
Just yesterday, November 4, 2026, Chainalysis took KYT offline. It did the same to its other address-screening products and its login page after it flagged abnormal activity. The company plans to bring KYT back online and fix screening the next day.
For now, the connection is mere speculation as none of the firms have publicly linked the two events.
A Chainalysis breach running in the background
Meanwhile, all through last week, Chainalysis was preoccupied with revealing a widening cyberattack. The firm has reported that an attacker obtained the personal details of all the users on its platform.
The blockchain analysis firm has advised users to reset passwords and rotate API keys. Among the affected customers are law enforcement, regulators, and national security bodies.
The attack was first reported on October 30, even though there was no evidence of theft of personal details at the time.
Chainalysis claims “offensive agentic techniques,” are responsible for the attacks, while saying the attack is completely different from the $6.3 billion Binance theft just last week, the largest crypto hack on record.
Why Coincheck is quick to rule out a hack
Coincheck’s antecedents make it easy for the company to rule out a hack. In January 2018, the company paused withdrawals when hackers stole about 500 million NEM tokens, or approximately $530 million. At the time, it was one of the biggest crypto thefts ever.
The firm said it will announce when the current issue is resolved and withdrawals reopen, and asked affected users to resubmit transfer requests after service returns.
cryptopolitan.com
