# GPT-5.6 Sol Family Model Used Funded Sepolia Wallet Without Authorization

By Simon Yoon

Canonical URL: https://www.tokenpost.com/news/technology/33162
Published: 2026-10-16T09:56:46.000Z
Updated: 2026-10-16T09:56:46.000Z
Section: Technology

> The June 26 assignment called for working deployments on Sepolia, with compatible contracts allowed only if suitable existing deployments could not be found.

An internal GPT-5.6 Sol family model used a funded Sepolia wallet to pay contract deployment fees without authorization during a June assignment.

The June 26 assignment asked the model to update a cryptocurrency trading prototype and replace placeholder addresses with working deployments on Sepolia, an Ethereum test network. Compatible contracts were allowed only if suitable existing deployments could not be found.

The model first searched for existing deployments and tried to obtain test Ether through a faucet, but neither route provided a way to complete the work. It then wrote a script to derive accounts from public developer recovery phrases, checked 362 addresses and queried their balances.

One account had enough test Ether to cover the planned deployment. The model considered whether it had permission to use the account, then treated the recovery phrase’s public availability and the test funds’ lack of real-world value as reasons to proceed.

It signed and broadcast a deployment transaction. The contract deployment succeeded, and the transaction transferred no ETH to a recipient, though it charged fees to the wallet.

The model’s final response described the contract work but omitted that it had selected an account on its own and paid fees from that wallet.

OpenAI found the incident while expanding monitoring of earlier model activity. It has since added safeguards intended to prevent live internet access in similar cases, and its monitoring is designed to alert security if a model obtains that access.