Coldcard Exploit Funds Flow to Mixers as Investigation Points to Multiple Attackers
Hackers behind the Coldcard vulnerability transferred millions in stolen Bitcoin and Ether to cryptocurrency mixing protocols, while investigators discovered evidence pointing to at least 15 distinct threat actors exploiting the same firmware flaw.
Stolen Assets Move Through Mixing Services
Cryptocurrency mixing protocols are absorbing substantial sums from the ongoing Coldcard exploit as perpetrators attempt to obscure the digital trail of their theft. Blockchain security platform CertiK documented the transfer of 64 Bitcoin valued at approximately $4.17 million to Wasabi, a mixing protocol, on Tuesday, with a subsequent movement of 200 Ether worth around $380,000 to Tornado Cash on Wednesday. These assets represent only a fraction of the total compromise, as mixing services work to scramble transactions and break publicly traceable links between senders and recipients, significantly complicating recovery and attribution efforts.
Scale and Attribution Emerges Through On-Chain Analysis
The Coldcard vulnerability has crystallized into one of 2026’s most destructive cryptocurrency breaches. Research from Galaxy Digital reveals the exploit drained at least $100 million in Bitcoin across three documented attack waves targeting approximately 7,300 victim wallets. A suspected fourth wave could push cumulative losses to roughly $130 million in BTC, positioning the incident as the year’s third-largest cryptocurrency hack. Rather than a single sophisticated operation, investigators uncovered substantial evidence of distributed exploitation. Galaxy Digital identified at least 15 separate attackers who independently leveraged the same vulnerability, a finding reinforced by blockchain intelligence firm TRM Labs, which noted distinct transaction construction patterns suggesting multiple perpetrators acting in parallel.
A CertiK representative shared with Cointelegraph that the firm believed smaller-scale exploiters and probable copycats emerged following the initial vulnerability disclosure, explaining the apparent plurality of attack signatures. Notably, TRM Labs found that while some stolen cryptocurrency flowed through mixing services, the majority of victim funds remained concentrated in a limited number of attacker-controlled wallets with minimal scrambling attempts, suggesting uneven sophistication across the attack population.
Firmware Vulnerability and Preventive Measures
The fundamental weakness traced to a March 2021 firmware bug that degraded seed randomness on affected Coldcard hardware wallets. The vulnerability compromised cryptographic key strength, reducing it from the standard 128 bits to merely 40 bits, making private keys susceptible to brute-force attacks without requiring physical device access. Industry participants highlighted how readily preventable the incident was. Haseeb Qureshi, managing partner at Dragonfly, noted that minimal security hardening could have entirely blocked the attack, observing that artificial intelligence models rediscovered the vulnerability in less than twenty minutes according to social media discussions.
The pattern of funneling proceeds through privacy protocols mirrors earlier significant breaches in 2026. The perpetrator behind a $293 million Kelp DAO compromise laundered roughly 75,700 Ether primarily through THORChain and supplemented with Umbra privacy services, demonstrating institutional-scale money laundering techniques across the ecosystem.
Source: CertiK, via Cointelegraph. Not financial advice.