At least $111 million in Bitcoin has been reportedly stolen following a significant exploit affecting Coinkite’s Coldcard hardware wallets. The incident underscores growing concerns regarding private key security within the cryptocurrency sector.
Further estimates, released by Galaxy Research last Friday, suggest potential losses could exceed $130 million. The root cause of the breach lies within flawed seed generation processes employed in affected Coldcard devices. This permitted attackers to reconstruct private keys and subsequently gain access to users’ Bitcoin holdings.
Blockaid, a provider of security services for wallets and exchanges, estimates that nearly 75% of funds lost due to cryptocurrency exploits during the first half of 2026 stemmed from compromised private keys. This figure represents over $1 billion in losses reported across H1 2026, mirroring a surge in incident numbers.
Ido Ben-Natan, CEO of Blockaid, highlighted the critical issue of controlling asset access, drawing parallels to traditional password security and private key management. He reportedly stated that “you have to either kind of constantly be paranoid or either outsource that decision making process to someone else.”
K33 estimates that more than 7,000 addresses were targeted by the exploit. The exact number of individuals impacted remains uncertain, with analysts suggesting the actual extent of the breach may represent “the tip of the iceberg.” Ben-Natan further cautioned that reported incidents represent only a portion of the total problem.
This event reinforces established trends within the cryptocurrency landscape – private key vulnerabilities account for a substantial proportion of losses. The incident is predicted to have occurred in the last week, following an interview conducted by Ido Ben-Natan with media outlet The Starting Block.
Written by Daniel Brooks
Security Desk
