A single number stored in the token's own contract: allowance[you][them]. While it is non-zero, that address can call transferFrom and move up to that much of your balance, at any time, without asking you again. It has no expiry, no counterparty obligation and no notification. The vault you approved cannot revoke it for you — only you can, with a transaction, from the same wallet.

No, and the site would be worse if it pretended otherwise. An allowance is the correct, standard and necessary mechanism, and there is no version of ERC-20 that works without one. The problem is not that it exists; it is that it is unlimited by default, permanent by default, and appears on nobody's security page. 19.7% of new approvals on this chain ask for no limit at all.

Nothing was taken and nothing could be. The proof runs the spender's own transferFrom through eth_call, which executes on a real EVM and then discards the resulting state. No transaction is signed, no gas is spent and no balance changes. What it establishes is that the transfer would succeed at that block, which is a fact about the chain rather than a guess about a token.

Because two negative controls run beside every proof: the same call for one unit more than the allowance permits, and the same call against a stranger's balance. Both must fail. In the published scan, 158 controls were run and 158 held. If one ever passes, the proof next to it is reported void rather than green, and the scanner exits non-zero and writes nothing.

Because exposure is min(allowance, balance). An unlimited allowance over an empty wallet takes nothing today. It takes everything on the day you are paid, without you doing anything, because the allowance is still there and nobody told you.

That is not advice this page is in a position to give, and it would cost you a transaction per approval. What the measurement supports is narrower: you are almost certainly carrying standing allowances you have forgotten, some of them unlimited, and you can see exactly which on the breach page. What to do about each one depends on whether you still use the spender, which only you know.

no canonical Postern vault is deployed — deploying costs gas from a wallet and this repository holds no key. The contract is compiled and executed on Robinhood Chain on every build — 24 of 24 properties, 12 of 13 deliberate defects caught — but no canonical vault exists. The app deploys one from your own wallet, and it is yours.

No. not audited by anybody; the sabotage suite is a self-review and says so. The sabotage suite is the strongest claim on this site and it is a claim about this suite: it says which defects these properties can see, and three of them could not see anything until the properties were fixed. That is a self-review, and the contract page says so in the same words.

Because a bastioned trace is the only thing anybody ever built whose sole purpose was to leave no ground unobserved, and solving it gives the site's argument in geometry before a token is mentioned. Fully manned, 3.9% of the approach is still dead ground. Take one gun of 12 off the wall and it is 10.0% — ×2.56, with not one stone moved. A postern is the small back gate: the ground in front of it is covered by 2 guns while somebody is standing there, which is exactly why it was cut into a curtain rather than anywhere else.

No, and there is no plan for one. There is no contract address to copy, no presale and no allocation.