Brazil's Largest Crypto Exchange Mercado Bitcoin Halts Withdrawals After $40 Million Hack

Mercado Bitcoin, Brazil's largest cryptocurrency exchange, has temporarily suspended deposits and withdrawals following a security incident discovered early on November 2, 2026.

The exchange confirmed that it had identified suspicious activity within one of its internal systems and immediately introduced protective measures.

According to blockchain security company Hypernative, more than $40 million in suspicious cryptocurrency transfers may be connected to the incident.

However, Mercado Bitcoin has not independently confirmed the estimated losses or disclosed how the attackers accessed its infrastructure.

The exchange maintains that customer funds remain safe and that no personal information was compromised.

The Exchange Says Customer Funds Remain Safe

Mercado Bitcoin reassured users that the security incident had been contained, emphasizing that customer balances and personal information were unaffected.

The exchange added that deposits and withdrawals had been suspended as a preventive measure.

Trading restrictions and withdrawal suspensions remain in effect, with no official timeline announced for restoring normal operations.

Mercado Bitcoin said it would continue providing updates through its official social media channels.

The company has not explained whether the affected infrastructure involved hot wallets, transaction processing systems or another internal component.

Security Researchers Trace $40 Million Across Blockchains

Blockchain security firm Hypernative identified more than $40 million in potentially suspicious transfers spanning at least ten blockchain networks.

The preliminary investigation includes transactions involving Bitcoin, Ethereum, Solana and Tron.

Mercado Bitcoin subsequently published a list of cryptocurrency addresses associated with the incident.

The disclosed addresses cover Ethereum-compatible networks, Bitcoin, Solana, Stellar and Tron, allowing blockchain investigators and other companies to monitor suspicious movements.

Publishing these addresses could help cryptocurrency platforms identify incoming stolen assets and restrict further transfers.

However, the precise amount stolen remains unverified, and the exchange has not disclosed the identity of any suspected attackers.

Tether Freezes $4.5 Million in USDT

Stablecoin issuer Tether has frozen more than 4.5 million USDT connected to the suspected Mercado Bitcoin attack, according to CEO Paolo Ardoino.

The frozen tokens represent approximately $4.5 million in dollar-pegged cryptocurrency.

Tether can prevent transfers from designated addresses by blacklisting the USDT held in those wallets.

This mechanism can help restrict the movement of stolen assets while investigations continue.

However, freezing cryptocurrency does not automatically recover the funds or return them to their rightful owners.

The reported intervention follows similar measures taken by stablecoin issuers during the recent Binance security incident.

Mercado Bitcoin has not disclosed whether additional assets have been frozen or recovered.

Second Major Crypto Exchange Incident in Days

The suspected Mercado Bitcoin breach comes just days after Binance suffered a reported $6.3 billion cryptocurrency hack on October 29.

US investigators attributed the Binance incident to North Korea's TraderTraitor hacking group, according to the FBI.

Binance subsequently reopened withdrawals and reported replacing approximately 95% of the affected customer assets.

However, there is currently no evidence linking the Mercado Bitcoin incident to the Binance attack.

Mercado Bitcoin has not identified the attackers or disclosed whether the breach involved similar vulnerabilities.

The two incidents nevertheless highlight the security challenges facing major cryptocurrency trading platforms.

For now, Mercado Bitcoin customers remain unable to deposit or withdraw assets, while the exchange investigates the suspicious transactions.

The company continues to insist that customer funds are protected, although independent verification of the reported losses remains pending.