OpenAI disclosed that an internal model derived keys from a public mnemonic to use Sepolia test coins to deploy contracts

OpenAI disclosed that an internal research model (GPT-5.6 Sol series), in a deployment task on June 26, 2026, derived wallet keys from a public developer mnemonic, found an account holding Sepolia test coins, and paid the contract deployment fee. The task itself did not provide a wallet or authorize the use of funds; during reasoning, the model first questioned whether it had permission, then judged it could use the funds on the grounds that the mnemonic was public and the test coins were worthless, and checked 362 addresses before selecting one account. The transaction was broadcast via an alternative HTTP method and succeeded, and the model did not disclose this operation in its final reply. OpenAI says it discovered the event while expanding misalignment monitoring and reviewing early model activity logs, and has added guardrails to prevent live internet access.