---
id: "CMP-202611-o62s3g"
kind: "campaign"
aliases: []
title: "Mercado Bitcoin, Brazil's largest crypto exchange, breached: about $46M drained from its wallets, deposits and withdrawals halted"
severity: "high"
cvss: null
epss: null
exploited: true
status: "open"
category: "vendor"
products: [{"name": "Mercado Bitcoin", "fixed": [], "vendor": "Mercado Bitcoin"}]
ecosystems: []
tags: ["campaign", "early-warning"]
not_affected_if: []
published_at: null
first_seen_at: "2026-11-02T23:06:02+00:00"
updated_at: "2026-11-02T23:06:02+00:00"
sources: [{"source": "analyst", "url": null, "first_seen_at": "2026-11-02T23:06:02+00:00"}]
---

# Mercado Bitcoin, Brazil's largest crypto exchange, breached: about $46M drained from its wallets, deposits and withdrawals halted

Mercado Bitcoin confirmed on 2 Nov 2026 that attackers got into 'one of our systems' early that morning and moved about $46.3M in crypto (Arkham data). Arkham says the attacker swept funds from older deposit addresses and is selling memecoins and altcoins. Tether froze more than 4.5M USDT linked to the attacker. The exchange paused deposits and withdrawals and says customers' funds and data were not affected. How the attackers got in and who they are: unknown. This is the latest in a run of crypto platform breaches (Binance, Polymarket, Chainalysis).

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- :Mercado Bitcoin affected ? fixed ?

## How to check

Check whether your organisation or treasury holds funds at Mercado Bitcoin or has pending deposits or withdrawals there. Check whether your wallets received funds from the destination addresses Mercado Bitcoin posted on X; the addresses are not in our sources. The way in is unknown, so there are no indicators for your own systems yet.

## Fix

Do not send new deposits to Mercado Bitcoin deposit addresses until the exchange says it is safe. Watch its official X account for when withdrawals resume and for its findings. If you received funds from the flagged addresses, freeze them and report them to the exchange.

## Timeline

- 2026-11-02T23:06:02+00:00 analyst

## Documents

- [describes] @techmeme.com: Brazil's largest crypto exchange Mercado Bitcoin halts withdrawals after a breac https://bsky.app/profile/techmeme.com/post/3mzefxyhij52f
- [describes] Mercado Bitcoin, Brazil's largest crypto exchange, hit by $46 million security breach https://www.theblock.co/news/defi/2026-11-02-mercado-bitcoin-hack-46-million-brazil-exchange-432333

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_