Key facts
- A wallet associated with the Coldcard hacker has received numerous small Bitcoin deposits with embedded messages.
- These messages are permanently recorded on the Bitcoin blockchain via the OP_RETURN function.
- The messages include pleas from victims to return stolen funds and offers from third parties to launder the money.
- The Coldcard exploit has resulted in confirmed losses exceeding $100 million.
A wallet linked to the individual responsible for the recent Coldcard exploit has become a public forum for communication, with users attaching messages to small Bitcoin deposits. These transactions, utilizing Bitcoin's OP_RETURN function, permanently inscribe sentiments onto the blockchain. The messages range from desperate pleas from victims seeking the return of their stolen funds to opportunistic offers from individuals proposing to launder the illicit gains for a fee. The wallet currently holds approximately $36 million in cryptocurrency. Blockchain researchers, including those from Galaxy Research, have identified the address as belonging to the Coldcard attacker. Since July 30, numerous transactions have carried these messages, with some users directly requesting specific amounts of Bitcoin back, while others use the platform for unrelated solicitations or abstract notes. This method of communication via OP_RETURN is not unprecedented, having been employed during the 2020 LuBian mining pool theft to attempt contact with the perpetrators. The Coldcard exploit itself has led to confirmed losses exceeding $100 million.