TLDR
- Mercado Bitcoin paused deposits and withdrawals on Nov. 2 after wallets were drained on at least 10 blockchains.
- Security firms estimate losses between $40 million and $46 million.
- Tether froze more than $4.5 million in USDT tied to the incident.
- The exchange says no customers were harmed and no data was breached.
- No group has been blamed, and no public evidence links it to the Binance hack.
Brazilian crypto exchange Mercado Bitcoin suspended deposits and withdrawals on Monday. The pause came after wallets tied to the platform were drained across at least 10 blockchains. Security firms estimate the loss at more than $40 million.
Another exchange, @MercadoBitcoin, has been hacked for over $46M!
Over $9M in stolen assets has already been frozen.
The hacker still holds the following altcoins, which could face selling pressure:
372.99B $PEPE ($1.79M)
12.82K $AAVE ($1.61M)
769.95K $PENDLE ($1.35M)
29.83K… pic.twitter.com/qRksDssA8Z— Lookonchain (@lookonchain) November 3, 2026
Blockchain analysts later put the figure above $46 million. The company is one of the largest crypto exchanges in Brazil. It had 4.5 million users as of July.
What Happened to the Wallets
Pablo Sabbatella, founder of security firm Opsek, relayed a report on the timing. The largest outflows hit between 06:19 and 06:53 UTC. Wallets on Ethereum, Solana, Tron, Polygon, Arbitrum, Avalanche, BSC, Stellar and other chains sent most of their funds to new addresses.
The report says the attacker now holds about 2,852 ETH, 106 BTC and 10,700 SOL. It also lists 6.7 million XLM, 77,000 AVAX and more than 200 other tokens. The transfers were plain transactions, not a smart contract exploit. How the attacker gained signing access is unknown.
Dickson Wu, a senior security engineer at Certik, shared an early post-mortem. He said the attackers “picked at eight small chains for four hours,” including Base, Optimism and Arbitrum. The attack then moved to the main hot wallets.
Wu said tiny amounts of Ether were then sent from 27,160 different addresses. He wrote that whoever did this can also move money out of the exchange’s customer deposit addresses.
Mercado Bitcoin said on X that it had “identified and swiftly contained” a security incident. It said customers were not harmed and no data was breached. The pause on deposits and withdrawals is a precaution while teams investigate and work with authorities.
Wu said funds kept moving out of the linked addresses hours after the suspension was announced. Thousands of small ETH transfers then went into a single address. A company spokesperson told Cointelegraph that customers had suffered no losses. The company did not respond to questions about the continued transfers.
Funds Frozen and Addresses Shared
Tether CEO Paolo Ardoino confirmed the company froze more than 4.5 million USDT linked to the incident. The announcement did not say the tokens were returned to Mercado Bitcoin. By 4:42 p.m. UTC, Tether and Circle had frozen about $6.2 million combined.
Tether froze more than 4.5M USDT related to this security incident. https://t.co/PCtP4957jn
— Paolo Ardoino 🤖 (@paoloardoino) November 2, 2026
About $20 million had moved into newly created wallets by that time. Over $20 million remained in addresses identified by Mercado Bitcoin, including all 106 BTC.
The exchange later published destination addresses on EVM chains, Bitcoin, Solana, Stellar and Tron. It said the list was meant for identification and tracking only. The disclosure did not give a dollar value for each address.
Brazilian outlet BitNotícias reported that security firm Hypernative flagged more than $40 million in suspicious transfers. Brazil’s central bank built a crypto threat alert system with Hypernative earlier this year. Mercado Bitcoin was named as a planned participant. The exchange did not say which alert system it used in this case.
The incident follows the Binance hack reported on Thursday. The FBI says North Korea’s TraderTraitor group stole over $6 billion from the exchange. Binance began resuming withdrawals on Sunday and said it had replenished 95% of the stolen assets.
No group has been blamed for the Mercado Bitcoin attack. There is no public evidence linking it to the Binance attack. A data breach could also trigger notice rules under Brazil’s data protection authority.
In September, Chile’s Orionx, another Tether-backed exchange, announced its closure. A forensic audit found more than $7 million in customer assets had moved to wallets outside its control. Tether announced a $20 million investment in Mercado Bitcoin in July.
In its latest update, Mercado Bitcoin said it is working to restore operations safely. It said deposits and withdrawals had not reopened. It will share further updates through its official channels.
