Metric | Value |
|---|---|
Suspicious transfers flagged | > $40M |
USDT frozen by Tether | > 4.5M |
Blockchains involved | at least 10 |
Networks with published addresses | 5 |
Mercado Bitcoin, Brazil's largest crypto exchange, suspended deposits and withdrawals on Monday, November 2, after a security incident in one of its systems. Blockchain security firm Hypernative flagged more than $40M in suspicious transfers across at least 10 blockchains, a figure the exchange has not confirmed.
What the exchange said
In a statement posted on X, Mercado Bitcoin said it "identified and quickly contained a security incident in one of our systems early this morning". It described the suspension of deposits and withdrawals as "a preventive protection measure".
- No customer lost money, according to the exchange
- No data leaked
- Teams are investigating, tracing assets and coordinating with authorities
- No date has been given for resuming deposits and withdrawals - updates will be posted on X
The exchange has not said which system was breached, how the attackers got in or how much was taken in total.
How much moved and on which chains
Hypernative's preliminary analysis spans at least 10 blockchains, including Bitcoin, Ethereum, Solana and Tron. The transfers of more than $40M may be linked to the incident, but Mercado Bitcoin has not published an official total.
In a follow-up post, the exchange published the destination addresses it identified on five networks: EVM chains, Bitcoin, Solana, Stellar and Tron. It said the addresses were released only so the funds can be identified and tracked on-chain.
Tether froze 4.5M USDT
Tether CEO Paolo Ardoino said on X that the issuer froze more than 4.5M USDT connected to the incident. A freeze blocks the tokens from leaving the flagged addresses, but it does not by itself return the funds to their owner.
Tether invested $20M in Mercado Bitcoin in July, when it said the exchange served 4.5 million users.
Four days after Binance
The incident comes four days after the October 29 attack on Binance, in which more than $6B was drained. The FBI attributed that theft to North Korea's TraderTraitor group. Binance has since resumed withdrawals and said it replenished about 95% of the affected assets.
Mercado Bitcoin has not linked the two incidents and has not said who is behind its own.