Mercado Bitcoin halts deposits and withdrawals after a security incident

Mercado Bitcoin suspended deposits and withdrawals on Monday, November 2, 2026, after detecting a security incident in one of its systems. Blockchain security firm Hypernative’s preliminary estimate is that the suspicious outflows exceed $40 million, an amount the exchange has not confirmed, while the exchange itself says customers suffered no losses and none of their data was leaked.

What did Mercado Bitcoin announce?

Mercado Bitcoin says it detected and quickly contained the incident, presenting the suspension of transfers as a precautionary measure. While it remains in place, customers cannot send funds to the platform or withdraw them from it.

According to its announcement on X, its teams are investigating the matter, monitoring the assets and coordinating with the relevant authorities. Bitcoin Magazine, citing Bloomberg, also reports that the company will absorb all losses.

Three key questions remain open, however: which system was breached, what the final size of the losses is, and when deposits and withdrawals will resume. The available reports contain no official answer and no timeline for restoring service.

Where does the $40 million estimate come from?

Hypernative’s estimate is based on suspicious transfers across at least ten blockchain networks, including Bitcoin, Ethereum, Solana and Tron. As CryptoPotato reports, the first was recorded at 02:15 UTC, and the bulk of the funds moved between 06:19 and 06:53 UTC to newly created addresses.

The transactions carried valid digital signatures, meaning they appeared to be authorized by the source wallets. That does not explain how the ability to sign them was obtained. Hypernative notes that the mechanism remains unknown and that it still has to confirm that every source address belongs to Mercado Bitcoin.

The exchange then published five destination addresses for identification and tracking. The Bitcoin address had received about 106 BTC, according to data from the mempool.space block explorer. Of these, 104.4 BTC arrived in a single transfer at 06:41 UTC, and as of 14:50 UTC the Bitcoin had not moved.

What funds did Tether freeze?

Tether froze more than 4.5 million USDT linked to the incident, according to a post by its CEO, Paolo Ardoino. USDT is a stablecoin, a cryptocurrency designed to maintain a stable reference value.

The intervention is also interesting because of the relationship between the two companies: Tether invested $20 million in Mercado Bitcoin in July, saying at the time that the exchange served 4.5 million users. Freezing funds, however, does not by itself confirm that they have been returned.

What does the suspension mean for users?

The immediate consequence for customers is that they cannot move funds, even if, as the company says, they have suffered no financial loss. For readers in Greece, this is an important distinction: having your losses covered and having access to your money are not the same thing.

The incident comes four days after the attack on Binance, with losses of $6.3 billion according to the sources. There is nothing in the available information, however, linking the two cases.

We see it as a positive that addresses were published so the funds can be tracked. Assessing Mercado Bitcoin’s response, however, takes more than reassurances: a confirmed accounting of the losses, an explanation of the breach and a clear timeline for recovery. That is what we will be watching from here on.