Exchange UserWallet (709k Fleet) — Bytecode Verification

Source code verification for Ethereum contract 0x24eb8813f35fa3f594d8060cd05ecb2c3ba068a7.

Part of Ethereum History — a project to recover and verify the source code of historically significant Ethereum contracts.

The Contract

This is an exchange deposit wallet — one of 709,039 contracts with identical runtime bytecode, making it the most deployed bytecode pattern in Ethereum history. Each contract was deployed as a dedicated deposit address for an exchange user. The deployer (0x17bc58b788808dab201a9a90817ff3c168bf3d61, nonce 121,422) was a high-volume exchange hot wallet.

• Address: 0x24eb8813f35fa3f594d8060cd05ecb2c3ba068a7
• Deployed: Block 4,850,028 (January 4, 2018) — peak ICO mania era
• Siblings: 709,039 contracts with identical runtime bytecode
• Deployer: 0x17bc58b788808dab201a9a90817ff3c168bf3d61 (nonce 121,422)

Functions

Selector	Function	Description
0x395ede4d	collectToken(address)	Sweep ERC20 token balance to owner
0x83197ef0	destroy()	Self-destruct, sending ETH to owner
0x8da5cb5b	owner()	Returns the owner address
0xe5225381	collect()	Sweep ETH balance to owner
(fallback)	function() payable	Accept ETH deposits

The owner (set to msg.sender at deploy time = the exchange hot wallet) could sweep funds at any time. Users deposited ETH or tokens, the exchange swept them into its treasury.

Match Result

Code match — the 627-byte runtime code is an exact bit-for-bit match. The CBOR metadata suffix differs (it encodes a Swarm hash of the source metadata including original filename and whitespace, which we cannot recover).

Compiler

solc 0.4.14 / 0.4.15 / 0.4.16
--optimize --optimize-runs 200

All three versions produce identical runtime bytecode.

Key Archaeology Findings

The source was non-trivial to reconstruct despite its simplicity:

1. modifier onlyOwner — The access control uses a Solidity modifier with old-style if (msg.sender != owner) throw, not the later require(). The modifier generates JUMPDEST merge points at the _ placeholder that produce the 5b 5b 56 opcode tail pattern in destroy() and collect().

2. Token t = Token(token) in collectToken — Caching the typed reference before calling balanceOf and transfer causes the compiler to keep an extra stack slot (the storage slot 0x00) throughout the function body. This generates the DUP2 SWAP1 before the CALLER opcode and the three-POP cleanup (5b 5b 50 50 50 56) instead of two.

3. pragma solidity ^0.4.11 — The contract accepts 0.4.11+, actual compiler was 0.4.14–0.4.16.

Verification

# Install solc 0.4.16
solc-select install 0.4.16
solc-select use 0.4.16

# Compile
solc --optimize --optimize-runs 200 --bin-runtime UserWallet.sol

# Compare output (strip CBOR metadata suffix before comparing)
cast code 0x24eb8813f35fa3f594d8060cd05ecb2c3ba068a7 --rpc-url https://mainnet.infura.io/v3/YOUR_KEY

The runtime code (stripping the a165627a7a7230...0029 CBOR suffix) matches exactly.

Attribution

Crack performed by EthereumHistory. Source submitted under the EthereumHistory open verification project.