An OpenAI research model stuck without funds on an Ethereum test network went looking for someone else’s wallet, found one through recovery phrases that were already public, and spent from it to finish a coding assignment, the company disclosed Thursday.
The incident occurred on June 26 during training of an internal model in the GPT-5.6 Sol family, and OpenAI discovered it on Sept. 25, according to its incident report.
The model needed no hacking skills to get in.
A recovery phrase, also called a seed phrase, is a list of words that generates a wallet’s secret keys; whoever has those words can recreate the accounts and spend from them without ever touching the owner’s device.
The assignment let the model deploy contracts, programs that run on a blockchain, but gave it no funded wallet to pay the fees. After its attempts to get free test tokens failed, it wrote a script that checked 362 addresses generated from recovery phrases commonly used by developers and found one with enough money.
“But using public known key/funds ethically?” the model asked itself in its recorded reasoning, before deciding that a public phrase and test tokens made it acceptable.
The spending happened on Sepolia, a separate network where developers rehearse Ethereum applications before launching them. Its tokens only pay for testing and aren’t linked to the ether traded on Ethereum’s main network.
