Slice on Base: the payout, the swap, and the limits of the onward trail

A transaction-level review of October 20-21, 2026. Public explorer records checked October 22, 2026. All times are UTC.

At 18:39:51 on October 20, a successful Base transaction paid 19,820.734002 USDC and 8.716935563284127414 ETH from the contract identified as Slice's FundsModule to the transaction sender. A subsequent swap returned 8.052201613921397406 ETH to that sender, which then transferred 16.788 ETH to another address. These are different stages of a route, not amounts to add together as separate losses.

The distinction becomes more important across chains. The public records establish five later Base departures and separate Ethereum receipts. They do not, by themselves, establish the bridge request linking each departure to an arrival, or how much of a mixed address's later activity belongs to this incident.

SlowMist's incident database describes a FundsModule issue involving release amounts returned by a caller-selected contract and reports an approximately US$41,000 loss. That is attributed incident context, not a loss estimate reproduced by this review. We did not replay the proposed mechanism or verify a patch. SlowMist incident record

What the initial transaction establishes

The seed transaction, 0x02b039…8d790a, succeeded in Base block 52,866,122. The USDC Transfer log records 19,820.734002 tokens from FundsModule 0x61bcd1…eacaaf to the sender, 0xc34572…8c892f. The independently retained RPC receipt matches the token contract, recipient, and integer amount. BaseScan's internal-transfer display separately shows an 8.716935563284127414 ETH payment between those addresses. Seed transaction

The transaction's top-level value is 0 ETH. That field measures the value submitted with the outer call, not all ETH moved by contracts during execution. It does not contradict the displayed internal payout. BaseScan also flags a reverted internal execution while marking the overall transaction successful; success should not be read as a claim that every nested call succeeded.

“Sender,” “FundsModule,” and “recipient” describe roles in the selected records. They do not identify a person or establish who controlled an address. The selected payouts are also not a complete reconciliation of the module's other transfers, user liabilities, or incident-wide net loss.

The swap changes the asset, not the amount of loss

At 18:41:17, the sender submitted 19,820.734002 USDC to the swap route. The token-transfer list also shows 0.000001 USDC returned to it. The resulting net USDC sent in that transaction is therefore 19,820.734001, not the full submitted amount. Swap transaction

The ETH records reconcile as follows:

• WETH unwrapped and passed into the payout route: 8.123274552931009529 ETH.
• ETH paid to the transaction sender: 8.052201613921397406 ETH.
• ETH paid to a separate recipient, 0xe25c63…272e42: 0.071072939009612123 ETH.

The two payouts sum exactly to the unwrapped amount. The separate recipient's role is not established here, so its payment is not labeled a gas fee or a proven service fee. The sender's ETH receipt is a payout, not a gas-adjusted profit calculation. Nor should the submitted USDC and the resulting ETH be counted as two losses.

Figure 1. The selected Base sequence, with the sender's actual ETH payout distinguished from the larger unwrap. Rounded ETH values carry an approximation sign; exact quantities appear in the text. The swap returned 0.000001 USDC. The later 16.788 ETH transfer came from an address that had also received pre-event funding. Sources: the seed, swap, funding, and onward-transfer records linked in this article.

Why 16.788 ETH is not an exact incident allocation

At 18:45:47, the sender transferred 16.788 ETH to 0xfba873…81364a. Before the seed, at 18:26:57, it had already received 0.0195 ETH from a different address. Both transfers are visible in BaseScan. Pre-event funding · Onward transfer

ETH is pooled in an address balance. These records show that the outgoing payment followed the incident receipts, but they do not assign an exact fraction of each prior receipt to it. We therefore report 16.788 ETH as an observed transfer, not as an independently measured amount of incident proceeds, a protocol loss total, or a recoverable balance.

Two chains, two levels of evidence

Between 23:57:03 on October 20 and 00:03:15 on October 21, 0xfba873…81364a sent five Base transactions with values of 0.5, 5, 5, 5, and 1.287 ETH. The explorer shows their route through 0x333573…4a3333 and internal transfers to an address labeled “Relay: Depository.” Their total is 16.787 ETH on the source side.

A SentinelTX working record pairs the first four departures with four Ethereum payments to the same hexadecimal recipient address. We independently checked the existence, successful status, amounts, recipients, and timestamps of those public transaction pages. The four source values total 15.5 ETH; the four cited Ethereum receipts total 15.496861123458983361 ETH.

The pairing itself remains a separate claim. The reviewed overview pages do not supply a request-level record that independently proves each cross-chain link. Nearby timestamps, similar amounts, and a matching destination address support a lead, but are not substitutes for that record. The fifth 1.287 ETH source transfer is observed; its destination correlation is not included in the four-pair total.

Figure 2. Individual source transactions and Ethereum receipts were checked in public explorers. Dashed links show pairings reported by the SentinelTX working record, not independently established request-level links. The fifth Base transfer is separate. Values on opposite chains are not added together as a loss figure.

Sources: the four Base and four Ethereum transaction pages linked in the exact-records appendix. Pairing provenance: SentinelTX working record; request-level linkage not independently established.

Explorer service labels help describe the displayed route. They do not establish ownership, complicity, or the intent of any service or address. This review does not turn the paired totals into an exact allocation of the earlier Slice payout.

Where this review stops

The firmest result is the transaction-level accounting: a USDC receipt and internal ETH payout, a subsequent swap with a small USDC return, and a later ETH transfer from an address with earlier funding. The cross-chain pages add independently observable records, while the request-level linkage remains qualified.

We do not establish an incident-specific exchange cash-out, a recovery, a current balance, or the identity of an operator. This is a selected-record review, not a complete address history. A missing finding is not proof that no further movement occurred.

Figure 3. Publicly checked transfers and unresolved attribution are different evidence categories. The initial USDC receipt also has an independent RPC check. A transfer's existence does not establish ownership or an exact share of commingled funds.

Sources: public BaseScan and Etherscan records linked in this article; retained RPC receipt for the initial USDC transfer. The diagram distinguishes observed transactions from unresolved attribution.

Sources and evidence appendix

This article is a new editorial reconstruction from the linked records, not an adopted or sealed SentinelTX report. Public explorer checks were performed on October 22, 2026. The independent RPC cross-check is limited to the seed receipt; it is not a replay of the full execution or an independent verification of every downstream internal call. Cross-chain pairing provenance is identified above. Automated aggregate totals from the working draft were not used as incident amounts or balances.

The article's scope ends at the selected transactions below, rather than at an asserted complete-history cutoff. The exact identifiers are provided so readers can distinguish an observed record from a proposed relationship between records.

Address register

• Transaction sender, Base: 0xc34572ebb26b9a4c54854aae8d2347108e8c892f
• FundsModule, Base: 0x61bcd1ed11fc03c958a847a6687b1875f5eacaaf
• USDC token, Base: 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913
• Onward recipient, observed on Base and Ethereum: 0xfba873b1e5d0256301b87ce74f79a30d6781364a
• Separate swap payout recipient, Base: 0xe25c6353a04f9375e9cbac224fda91a90c272e42

Exact cross-chain records

The pair numbering follows the working record, not an independently authenticated bridge-request mapping.

• Reported pair 1: Base 0.5 ETH, 0x6ca60f5873a2290cf7284146b4f87ab673d51183d3ba5503ab606774b17e75bb; Ethereum 0.499890262307287644 ETH, 0x4c02a7aa31c6f05662211d69d1031e5f51b5bfc350d01143aba6bb89022abde0.

• Reported pair 2: Base 5 ETH, 0xa05f56d4fc8484ab69ebbeb4ac4d28e40de98a8eea7244c2dcf2ed5b20b41c86; Ethereum 4.998990272562388387 ETH, 0x7125d47d1d734c5f1c253170fd1edaa72d1901c61ea3902f46e2604682150609.

• Reported pair 3: Base 5 ETH, 0x4ab516ee7fdca7b0985a132182412f6a860051bebc6e25f5b06db8cb8d37b4f6; Ethereum 4.998990251886325914 ETH, 0xe7ecbc6d35d72e1ec95ea16ae9491b410bff6dfb5e833b6c8c2baefffd33c212.

• Reported pair 4: Base 5 ETH, 0x485808ce7f4fb6f087072b179decd40aebc1177397488ababfffc8a4f8cb3d1e; Ethereum 4.998990336702981416 ETH, 0xdca2cb6c3fe5542d0447b5a98f2318b62a5a5b8b5090ebdac071fa20b34c9934.

• Fifth source only: Base 1.287 ETH, 0xb7ff77b677a67d251052557f8c514daaec0b013d1c31142b8674fece02796050. Destination correlation remains unconfirmed in this review.