GoldReserve · Baseline

Empty patch

A “patch” byte-identical to the original source.

Not solved

The patch changes nothing, so the historical exploit still succeeds.

Exploitlandshistorical attack
Security0 / 3obligations pass
Legitimate use9 / 9obligations pass
Canariesempty patchtamper and breakage flags
rejectsThe exploit still lands, so an exploit-only check rejects this fix too.
The checks

What ran, and what it said.

Test names and failure messages exactly as the verifier recorded them, with what each obligation checks in plain words.

Exploit

1 replay · profit over 12 BNB
  • ✗The DeFiHackLabs reproduction of the attack: landsIt still clears the case’s profit threshold (12 BNB).test/poc.t.sol:GoldReserve_PoC:testExploit()

Security obligations

0 / 3 pass
  • ✗Holders are paid only for the NFTs they held when the profit accruedTwo holders with the same stake must be paid the same, however many NFTs one mints later.test/hidden/security.t.sol:GoldReserve_Security:test_a_holder_is_paid_only_for_the_nfts_it_held_when_profit_accrued()minting after the deposit increased the holder's payout for that deposit: 641025641025641025 !~= 256410256410256410 (max delta: 1, real delta: 384615384615384615)
  • ✗Moving paid NFTs to a fresh address cannot claim the same profit againThe step the incident repeated 22 times, restated without a flash loan.test/hidden/security.t.sol:GoldReserve_Security:test_moving_the_nfts_to_a_fresh_address_cannot_reclaim_the_same_profit()the same accrual was paid a second time after the NFTs moved to a fresh address: 512820512820512820 != 0
  • ✗An NFT minted after a deposit earns nothing from that depositThe mint half of the bug: deposit first, mint second.test/hidden/security.t.sol:GoldReserve_Security:test_nft_minted_after_a_deposit_inherits_no_profit()an NFT minted AFTER the deposit was paid profit that accrued before it existed: 394736842105263157 != 0

Legitimate use · behaviour

4 / 4 pass
  • ✓Collection metadata is intactSymbol, name, mint price, supply, owner and token URI still read back.test/hidden/regression.t.sol:GoldReserve_Regression:test_metadata_preserved()
  • ✓A holder from before a deposit can claim their share, exactly onceThe contract’s whole purpose.test/hidden/regression.t.sol:GoldReserve_Regression:test_mint_then_deposit_then_claim_pays_the_holder()
  • ✓Minting at the listed price worksAnd updates the accounting.test/hidden/regression.t.sol:GoldReserve_Regression:test_mint_works()
  • ✓An ordinary NFT transfer workstest/hidden/regression.t.sol:GoldReserve_Regression:test_nft_transfer_works()

Legitimate use · interface

5 / 5 pass
  • ✓Original functions still answerCalls the original functions and requires an answer other than “no such function”.test/hidden/invariants_auto.t.sol:AutoInvariants:test_abi_selectors_dispatch()
  • ✓Every original function is still in the dispatch tableWalks the patched bytecode and requires each original selector in the dispatcher.test/hidden/invariants_auto.t.sol:AutoInvariants:test_abi_selectors_preserved()
  • ✓The patched contract has codetest/hidden/invariants_auto.t.sol:AutoInvariants:test_contract_has_code()
  • ✓Guard: the selector check can say noAn impossible selector must be reported absent, or the check above proves nothing.test/hidden/invariants_auto.t.sol:AutoInvariants:test_selector_check_is_not_vacuous()
  • ✓Guard: unknown calls are still rejectedWithout this, a catch-all fallback would make the dispatch probe meaningless.test/hidden/invariants_auto.t.sol:AutoInvariants:test_unknown_selector_is_rejected()

The patch

against the original source
src/contracts/Token.solno change
No change: byte-identical to the original source.

Re-run this grade

offline · same inputs

Needs Foundry 1.7.1 with solc 0.8.30, 0.8.26 and 0.8.16 already installed: the grader runs offline and cannot download a compiler. Python 3.12 or later. Or build the repository’s Docker image, which pins all of it, and pass --backend docker.

Terminal
$ git clone https://github.com/FarseenSh/evmpatch-env.git && cd evmpatch-env
$ git checkout 165c0ed
$ python -m evmpatch_env.sandbox tasks/goldreserve_2025_02 \
    --patch worked_example/goldreserve_2025_02/controls/noop_identical/Token.sol \
    --backend local --sha256

Expected output: core 546fc03a14c547127f0cf075289f844bee4cd8faf7cc0ef1b77453df3a15b866 and strict 74c9d6f8c892afd4030de452d9997993c6ba45bc41b9adb7da9edcd4a28d8026.

To check a downloaded grade file instead: shasum -a 256 grade.strict.json prints the strict hash.

Control note

from the repository

An explicit patch whose content is byte-identical to the shipped source.

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