# Block Inc.

Type: Company (SQ)

Source: Cyber Intelligence Brief — https://getcyberbrief.com/entity/block-inc-company
Canonical HTML page: https://getcyberbrief.com/entity/block-inc-company

## Timeline

- **2026-08-03**: Public disclosure and advisory — Block’s Bitcoin Engineering and Security team releases a security advisory revealing the entropy-generating coding flaw in Coldcard. Coinkite issues a firmware update that fixes the vulnerability for new wallets but warns that existing wallets remain vulnerable.
- **2026-07-31**: Additional theft waves detected — Galaxy Research identifies two further suspicious transaction sequences, bringing total estimated losses to nearly $89 million.
- **2026-07-30**: Initial mass theft — Attackers drain over 1,000 BTC from 1,196 wallets in 41 minutes, initially valued at approximately $70 million.

## Recent coverage (2 stories)

### Coldcard entropy flaw lets hackers steal $89M in BTC from 1,200 wallets in 41 minutes
2026-08-04 02:01:51 · Sentiment: Very Bearish · Impact: 8/10 · Sources: 3

A predictable recovery phrase vulnerability in Coldcard hardware wallets enabled a highly automated attack, draining $89 million from 1,200+ addresses in under an hour. The flaw, disclosed by Block’s security team, highlights critical supply-chain risks in entropy generation for embedded devices.
Full story: https://getcyberbrief.com/story/coldcard-entropy-flaw-89m-btc-heist

### Coldcard hack drains 1,367 BTC: predictable seed phrases expose $86M
2026-08-04 00:24:44 · Sentiment: Bearish · Impact: 7/10 · Sources: 2

The Coldcard vulnerability demonstrates how flawed random-number generation can compromise hardware wallets, a critical lesson for cryptographic security. Over 4,500 wallets lost $86M in Bitcoin as attackers reverse-engineered deterministic seed phrases. This ongoing breach forces a reevaluation of cold storage trust assumptions.
Full story: https://getcyberbrief.com/story/coldcard-hack-drains-1367-btc-predictable-seed-phrases

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