Mercado Bitcoin Pauses Crypto Deposits and Withdrawals After Security Incident
Brazilian exchange Mercado Bitcoin temporarily suspended crypto deposits and withdrawals after reporting a security incident. The company said it contained the issue and customers suffered no loss. A preliminary estimate from a third party put suspicious transfers at more than $40 million, but that figure does not show how much, if anything, was stolen.
- Transfers paused: Mercado Bitcoin said it suspended them as a precaution while investigating.
- Losses unconfirmed: Hypernative reportedly flagged more than $40 million in suspicious transfers from wallets attributed to the exchange.
- Cause unknown: The exchange has not identified the affected system or explained how access was obtained.
- Customer assurances come from the company: Mercado Bitcoin said customers suffered no loss and personal data was not exposed.
What Mercado Bitcoin has said
In a statement published by BeInCrypto, Mercado Bitcoin said it had detected a security issue in one of its systems and contained it quickly. The exchange paused crypto deposits and withdrawals as a precaution while its security teams investigated, traced potentially affected assets and coordinated with authorities.
“We detected and quickly mitigated a security issue in one of our systems this morning.”
Mercado Bitcoin said customers suffered no loss and their personal data was not compromised. Those claims come from the exchange. Reporting by BeInCrypto and Shattered.io does not include an independent audit or forensic finding to confirm them. The statement also does not say whether the exchange lost any of its own assets.
The exchange later said it was working to restore operations safely and would post updates through its official channels. The reports cited here do not give a calendar date for those updates or a timeline for resuming transfers. Customers should check Mercado Bitcoin’s official channels for the latest service status.
What the $40 million estimate means
Shattered.io attributed a preliminary estimate of more than $40 million in suspicious transfers to blockchain security firm Hypernative. The estimate refers to the reported value of on-chain transfers from wallets attributed to Mercado Bitcoin. It is neither an independently verified amount removed from the exchange nor a confirmed loss total.
BeInCrypto named nine networks associated with the activity: Bitcoin, Ethereum, Solana, Tron, Polygon, Arbitrum, Avalanche, BNB Smart Chain and Stellar. Shattered.io described activity across “at least 10” networks, but also named nine. The reports did not identify an additional network.
Shattered.io also reported that Hypernative’s preliminary inventory included approximately 2, 852 ETH, 106 BTC, 10, 700 SOL and 6.7 million XLM, plus more than 200 other tokens. These are early third-party figures, not an inventory confirmed or audited by the exchange. The dollar value of the assets can also shift with market prices.
A security incident, not yet a confirmed hack
Mercado Bitcoin called it a “security issue” and a “security incident.” So far, the available information does not show that a specific exploit occurred, which system was affected or how anyone gained the ability to move funds.
BeInCrypto reported that the transfers appeared to carry ordinary wallet signatures, the cryptographic approvals normally attached to valid transactions. That does not show who controlled the signing keys or how access was obtained. Compromised keys or weaknesses in withdrawal authorization are possible explanations, but neither has been confirmed.
Activity across several blockchains could point to a shared system for controlling wallet keys being affected. A multi-chain pattern alone does not prove there was a common vulnerability. The technical cause remains unknown.
Key questions and answers
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Why did Mercado Bitcoin pause deposits and withdrawals?
The exchange said the pause was a precaution while its teams investigated the incident and traced potentially affected assets. Tether froze more than 4.5 million USDT linked to the incident.
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Did customers lose funds or have personal data exposed?
Mercado Bitcoin said customers suffered no loss and personal data was not compromised. The reports cited here do not independently verify those claims.
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Was more than $40 million stolen?
That has not been established. Hypernative reportedly estimated more than $40 million in suspicious transfers from wallets attributed to the exchange. The figure is not a confirmed loss.
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What caused the incident?
The affected system and how access was obtained remain unknown. No specific exploit has been confirmed.
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When will transfers resume?
The updates cited here do not give a reopening date. Customers should check Mercado Bitcoin’s official channels for a dated update on restoring services.
A temporary pause can limit further movement while an exchange investigates, but it also leaves customers unable to move crypto through the platform. The key questions now are whether assets were actually lost and when customers can safely use normal transfer services again.
