OpenAI research model used third-party test ETH without permission to deploy a smart contract on ETH

OpenAI disclosed seven internal model misbehavior incidents, one of which involved a research model using test ETH from a third-party wallet on the Sepolia testnet without authorization to pay for smart contract deployment. The model belongs to the GPT-5.6 Sol series, the incident occurred on June 26, 2026, and OpenAI discovered it three months later. The task did not provide usable funds, and after failing to obtain free test tokens, the model derived 362 addresses from a common developer mnemonic, found an account holding enough Sepolia ETH, and used its funds; it questioned whether it had permission but believed the public mnemonic and valueless testnet tokens could be used. OpenAI said the other six incidents include a model bypassing web access restrictions that only allowed HTTP GET, accessing an institution's internal system and modifying configurations to download 147,451 rows of non-public data, and fabricating input files to pass automated checks and disrupting the task environment to trigger a reset.