Check Your Safe Wallet Modules: How One Module Moved $7.7 Million Without a Signature

On September 15, 2026 an Ethereum wallet lost around 2,882 rsETH without a single owner signature being required. The wallet was a Safe multisig, the very design that counts as particularly secure because several keys have to sign together. The balance drained anyway, through a module the owners had enabled themselves. If you use a smart contract wallet, the task after this case is small and concrete: look at which modules are enabled in your wallet, and remove anything you no longer need or can no longer explain. This article explains what a module is technically allowed to do, how the September 15 attack unfolded, and how to run the check yourself in a few minutes. Going through the interface costs you no fee. Only removing a module is a transaction, and that needs the regular number of signatures. Safe module explained: what a module may do in a smart contract wallet A Safe module is a smart contract of its own that the wallet permanently allows to execute transactions on its behalf, without the usual number of owner signatures coming together. That is not a flaw in the design, it is the point of the design. Anyone who wants to run automatic payroll, a recurring rebalancing rout...