Brazil’s Mercado Bitcoin Exchange: Self-Custody Wallet Alternative

On November 2, 2026, large unauthorized outflows from Mercado Bitcoin wallets across at least 10 blockchains triggered a major security incident.

Mercado Bitcoin is Brazil's largest crypto exchange. It suspended all deposits and withdrawals after the attack.

Blockchain security firm Hypernative flagged the transfers and estimates that more than $40 million left exchange-controlled addresses. Mercado Bitcoin has not confirmed this figure.

The attack hit Ethereum, Solana, Tron, Polygon, Arbitrum, Avalanche, BNB Smart Chain, Stellar, Bitcoin, and other networks.

What we know so far

• Timing. The largest outflows hit between 06:19 and 06:53 UTC, according to a report relayed by Opsek founder Pablo Sabbatella.
   
• Method. The attacker sent plain transactions. This was not a smart contract exploit, and the way the attacker got signing access is still unknown.
   
• Stolen assets. The attacker reportedly holds about 2,852 ETH, 106 BTC, 10,700 SOL, 6.7 million XLM, 77,000 AVAX, and more than 200 other tokens.
   
• Exchange response. Mercado Bitcoin says it "identified and swiftly contained" the incident. The exchange reports no harm to customers and no data breach.
   
• Tracking. Mercado Bitcoin published the attacker's destination addresses on EVM chains, Bitcoin, Solana, Stellar, and Tron. Tether CEO Paolo Ardoino confirmed a freeze of $4.5 million in USDT linked to the hack.
   
• Attribution. No group has claimed or received blame. No public evidence links the attack to the $6.3 billion Binance hack that the FBI attributed to North Korea's TraderTraitor group.

The key takeaway for users

Mercado Bitcoin says customers are not harmed. The exchange has not yet published a full account of the incident or a date for resuming withdrawals.

Until then, users cannot move their funds. This is the core risk of keeping significant holdings on a centralized exchange.

The principle "not your keys, not your coins" remains highly relevant for long-term storage.

Once withdrawals resume on Mercado Bitcoin, transfer assets to self-custody and reduce exposure to exchange-level incidents.

How to move from Mercado Bitcoin to Tangem Wallet

1. Download the Tangem wallet app on your phone.
    

2. Create a Mobile Wallet. You can back it up with a seed phrase, iCloud, or Google Drive, or with a Tangem hardware wallet (recommended).

   

3. Tap Add funds to add tokens you need, e.g., BNB. You can also use the search bar.
    

   

4. Select the token, choose the network you want to receive it on, e.g., Binance Smart Chain, and tap Confirm.

   

5. Tap Receive to get the public address. 

   

   6. Tap Copy to copy the address to your clipboard. Then go to the Mercado Bitcoin withdrawal page.

   

 

Withdrawing from Mercado Bitcoin (once withdrawals resume)

1. Log in to Mercado Bitcoin and open your crypto balance.
    
2. Select the coin you want to withdraw.
    
3. Tap Withdraw and choose the crypto withdrawal option.
    
4. Paste the Tangem address you copied into the Address field.
5. Select the identical network.
6. Enter the amount. You can choose Max to send it all.
7. Review all details carefully (address, network, amount).
8. Confirm the withdrawal. Mercado Bitcoin may ask for a 2FA code or an email confirmation.
9. Once confirmed, the exchange processes the withdrawal. The status changes to "Processing."

 

⚠️ Warning. A wrong network causes permanent loss of your funds. Make sure that you select the same network on Mercado Bitcoin as you did on Tangem.

Also beware of phishing. Attackers often send fake "withdrawal reopened" emails after an incident, so use only the official Mercado Bitcoin app or website.

 

Open the Tangem app and check your balance. Your funds appear after the network confirms the transaction. Confirmation times depend on the network:

• Bitcoin: 10 to 60 minutes.
• Ethereum: 5 to 20 minutes.
• USDT on TRC-20: 2 to 3 minutes.
• Solana: less than 30 seconds.

If the funds do not arrive, find the transaction hash in your Mercado Bitcoin withdrawal history. Paste the hash into a blockchain explorer to check the status. The explorer shows whether the transaction is confirmed or still pending.

Tips for safe withdrawals

Use these tips to withdraw safely and pay less.

1. Send a small test amount first. Send a small amount, confirm it arrives, then send the rest.
    
2. Whitelist your Tangem address on Mercado Bitcoin. A whitelisted address speeds up future withdrawals faster.
    
3. Withdraw during low-traffic hours. Network fees on Ethereum drop when the network is less busy.
    

Why Tangem?

Self-custody means you control your own keys. No exchange and no regulator can freeze your funds or pause withdrawals.
 

Tangem gives you clear advantages:

• Seedless backup. You can decide not to use a seed phrase.
   
• Card format. The wallet is a card you can carry in your pocket.
   
• Broad token support. Tangem supports 90+ blockchain networks in one app.
   
• Secure chip. The card holds your keys on a secure element with EAL6+ certification.
   
• Self-custody. Tangem does not store, access, or control your funds or keys.
   
• Tap to sign. You tap the card to your phone and approve each transaction.
   
• No battery or cables. You need only a card and your smartphone.
   
• Tough build. The wallet carries an IP69K rating for dust and water.
   
• In-app swaps. Tangem aggregates prices from DEXs, CEXs, and bridges so you get the best when swapping between tokens.
   
• dApp access. WalletConnect links your wallet to DeFi and NFT apps.
   
• Native staking. You can stake ATOM, BNB, GRAM (formerly TON), POL on Ethereum, SOL, TRX, ETH, and ADA.
   
• Tangem Pay. Tangem Pay lets you spend stablecoins through a Visa card in supported regions.
   
• Zero-fee stablecoin swaps. Tangem charges 0% commission on eligible stablecoin-to-stablecoin swaps.
   
• Yield Mode. You earn yield on your stablecoins from inside your self-custody wallet.
   
• Audited app. The Tangem app is open source and independently audited.