Massive Bitcoin Heist Raises Alarms Over Coldcard Vulnerability

A significant security flaw has been uncovered in Coldcard hardware wallets, resulting in the theft of over $130 million worth of Bitcoin. This alarming breach is recorded as one of the largest crypto hacks in 2026, showcasing vulnerabilities in systems relying on hardware security.

Weakness in Wallet Security Unveiled

A firmware update in Coldcard wallets diminished the security strength of key generation, reducing it from 128 bits to a mere 40 bits. This change allowed cybercriminals to use brute force methods to easily compromise the keys. Galaxy Digital reports an impact on approximately 7,300 wallets, with suspicions that more coordinated attacks are on the horizon.

What Are Users Doing?

Blockchain analytics from Glassnode reveal that Bitcoin’s daily active user count soared to new highs, attributed to a collective rush to secure funds. Efforts by large stakeholders and individuals alike to transfer assets to safer wallets have significantly driven network activity, indicating security concerns rather than renewed interest in Bitcoin.

In a dramatic incident on July 31, hackers made off with 594 Bitcoin worth millions, contributing to the overall loss of over 1,596 Bitcoin through multiple attack waves.

• Approximately 7,300 wallets compromised across three major attack waves.
• Over 1,596 Bitcoins stolen with financial losses climbing.
• Fourth attack wave suspected but not yet confirmed.

Blockchain security company CertiK noted that hackers used privacy platforms like Wasabi and Tornado Cash to launder stolen funds, complicating the tracing process. Indications of numerous hackers involved highlight the threat’s complexity, prompting an urgent response from cybersecurity experts.

CertiK analysts stated that some of the suspect transactions may be unrelated to the main exploit group. The firm noted, “There’s likely a few copycats after the initial exploit.”

Dragonfly’s Haseeb Qureshi observed that artificial intelligence could have detected the flaw almost instantly, suggesting missed preventive opportunities. Consequently, security advisors are urging affected users to abandon compromised Coldcard wallets, emphasizing that only the creation of new wallets will ensure full safety.

Based on confirmed on-chain losses, the Coldcard incident ranks as the third-largest cryptocurrency hack of 2026, trailing only behind two major exchange breaches this year.