Mercado Bitcoin Freezes Deposits After Suspected $40M Hack

Brazil's largest crypto exchange paused deposits and withdrawals after a dawn security scare. Monitors flagged about $40 million in odd transfers tied to a Mercado Bitcoin hack. The firm has not posted a loss total.

Mercado Bitcoin said on Monday that it found and stopped a security incident overnight. It claimed no client losses and no data leak. As a safety step, it froze deposits and withdrawals. Staff are tracing assets and talking with authorities.

Brazilian outlet Exame said security firm Hypernative linked exchange-linked wallets to more than $40 million in outflows. That is about R$217.7 million at then-current rates.

What Mercado Bitcoin Confirmed

In its X note, Mercado Bitcoin said teams are probing the case. They are tracking assets and working with authorities. It vowed regular updates on official channels.

A later post shared destination addresses from moves tied to the incident. The list is for tracing only. The EVM address is 0xe485e7A70b1131216Cb47CA4555c4Bbb2C742478. The Bitcoin address is 19qGpsHvzh1t6pVi526XNNkh6hW6prDZp. The Solana address is 3YX6WHncP1Ra4AotE9YLawFt4nPmxyux288FWXkEW97J. The Stellar address is GDXYRI6IONQA5YTGRLQ603FGJ2BWXPJTTQPUXFPSEXSRKBZLFKMZSOLP. The Tron address is TEX3HuDRHRa3tnYpy96M4UfSx62VhDyA5L.

The firm said it is still working to restore service safely. Its status page showed login, app, signup, and Trade API trouble that morning.

On-Chain Flags Behind the Mercado Bitcoin Hack

Hypernative's early view, via Exame, pointed to large balances at addresses later mirrored by Mercado Bitcoin. The pile included about 2,852 ETH and about 106 BTC. It also held thousands of SOL, millions of XLM, and tokens on Avalanche, XDC, Tron, and more than 200 other assets.

Public Bitcoin data matches one slice. Address 19qGpsHvzh1t6pVi526XNNkh6hW6prDZp shows about 106.07 BTC across seven transfers. The coins were unspent at check time on the public Bitcoin chain. A Solana view of the named destination showed about $1.5 million in tokens, led by USDT.

Exame also said Tether blocked nearly $3.7 million in USDT on probed addresses. That freeze stops further stablecoin moves. It does not bring back the rest of the mixed haul.

Chain snapshots alone do not prove every coin came from Mercado Bitcoin custody. They do show why the firm posted destinations and asked the market to watch them.

Why the Freeze Matters

Why did it matter? Brazil's biggest retail crypto venue hit the classic exchange-heist sequence. Overnight scare. Deposit and withdrawal freeze. A client-safety line. Then destination wallets for the chase.

Users cannot move funds while the rails stay shut, even if balances look fine. Regulators will want a clear tech account when withdrawals return. Issuers and platforms will watch whether more flagged coins get frozen before mixers or OTC desks.

The timing raises the stakes. The Mercado Bitcoin hack note landed days after a multi-billion hot-wallet drain elsewhere. Different scale. Same lesson. When custody keys or signing rails fail, the first move is to stop the bleed. Then the money race starts across chains.

New rails change the surface of theft. The custody problem stays old. Until Mercado Bitcoin reopens deposits and withdrawals and explains what failed, the $40 million figure stays an analyst estimate beside an official freeze.