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FIGR_HELOC $1.05 Hacks & Security · Explained
Mercado Bitcoin to cover customer losses and reopen in phases after hack
The Brazilian exchange says users will not bear losses from the Nov. 2 breach, with read-only account access returning first and trading still paused.
Key takeaways
- Phased return. Customers get read-only access first; transfers, withdrawals and trading resume later, subject to independent security testing.
- Company-funded cover. Mercado Bitcoin says it will replenish affected assets from its own balance sheet and is preparing repurchases in domestic and international markets.
- Disputed total. The exchange's accounting and an outside analyst's estimate differ by at least $8 million and have not been publicly reconciled.
What happened
Mercado Bitcoin will begin returning account access to customers on Monday, the Brazilian exchange said, after a security breach forced it to halt deposits, withdrawals and trading. In the first phase, users will be able to sign in through the company's website to review balances, statements, holdings and investments. Moving funds and trading will remain switched off until later stages, which the company said depend on independent security testing.
The exchange has not committed to a firm date for full service. It said operations would resume once complete security conditions are in place, and that any timetable would be announced only through its official channels. Mercado Bitcoin also advised customers to disregard unsolicited messages from people presenting themselves as its support staff.
Alongside the staged reopening, the company promised to absorb the cost of the breach, saying it would use its own funds to replace affected assets and that its trading desk was preparing repurchases in domestic and international markets. Mercado Bitcoin told Cointelegraph that more than $15 million of the stolen funds had already been frozen with help from partners across the industry.
First $85.8KLatest $80.5K-6.2% over the period
Points are daily observations, not closing prices.
Why it matters
Mercado Bitcoin is among Latin America's largest crypto platforms, serving roughly 4.5 million to 4.8 million customers, and the outage left them unable to trade or move funds while markets continued to move. Its commitment to make users whole shifts the loss onto the company's balance sheet regardless of how much is eventually recovered. The incident also draws attention to how exchanges protect the credentials that authorize transactions: investigators describe the attack as a compromise of signing access rather than a flaw in a smart contract, meaning the attackers did not have to defeat blockchain cryptography to move assets.
What the data shows
Public estimates of the damage diverge. Bitcoin.com News reported that the company acknowledged about $38 million in affected digital assets, while Arkham Intelligence analyst Emmett Gallic put suspicious transfers at more than $46 million, at least $8 million above the official accounting. The two figures have not been reconciled in public. On containment, the exchange said it had blocked $11 million with the help of Tether, Circle, Paxos, BRL1 and Chainalysis, and that other amounts eligible for blocking had been identified. A Bitquery analysis cited by Bitcoin.com News traced suspicious activity across Ethereum, Bitcoin, Solana, Stellar, Arbitrum, Tron and Polygon.
Background
Founded in 2013 as a bitcoin brokerage in São Paulo, Mercado Bitcoin expanded into a diversified fintech offering spot trading, staking, tokenized private credit and payment services, and has reported cumulative transaction volume above 215 billion Brazilian reais. SoftBank invested $200 million in 2021 in a deal that valued the business at about $2.1 billion. The breach was identified in the early hours of Nov. 2, when the company suspended services as a precaution, activated internal security procedures and said it had notified the authorities. Tether has separately put $20 million into the company to support operational expansion, an investment Mercado Bitcoin cited when addressing liquidity questions.
What is still unclear
The precise entry point of the intrusion has not been established. It is also unclear whether the competing loss estimates cover the same transactions and asset categories, how much of the remaining total can be blocked, and whether frozen stablecoin balances will be returned to the exchange or to customers. Restricting a token does not by itself restore it to its owner, and recovery may depend on custodians and legal authorities.
What to watch
The next test is operational: whether independent security checks support a staged return of withdrawals and trading, and whether the exchange can demonstrate that the controls around transaction signing have been rebuilt. Recovery work with stablecoin issuers and blockchain investigators, along with any regulatory response in Brazil, will shape how quickly customers regain full access to their accounts.
Questions readers ask
Will Mercado Bitcoin customers lose money in the hack?
The exchange has said users will not bear losses from the incident and that company funds will be used to replace affected assets. It has not published a final figure for the total cost.
When will withdrawals and trading resume?
No date has been set. Viewing balances and statements comes first, and transfers, withdrawals and trading return in later phases once independent security testing is complete, according to the company.
How much was taken?
The exchange has acknowledged roughly $38 million, while Arkham Intelligence analyst Emmett Gallic estimated more than $46 million in suspicious transfers. The gap of at least $8 million has not been publicly explained.
