QA Report

Impact RubiconRouter.swapEntireBalance is supposed to buy at least buyamtmin of Y output tokens by using the caller's entire X input token balance. The problem is that instead of passing the buyamtmin minus the fee to swap, the code uses the caller's X token balance, maxAmount. This means the cal...

Reentrancy attack

Lines of code Vulnerability details Impact High impact. Reentrancy Attack may lead in lost of funds. Proof of Concept Reentrancy in RubiconMarket.matchouint256,ERC20,uint256,ERC20,uint256,bool c ontracts/RubiconMarket.sol1049-1108: External calls: - buybestmakerid,minmpayamt,t...

BathPair.sol#rebalancePair() can be front run to steal the pending rebalancing amount

Lines of code Vulnerability details function underlyingBalance public view returns uint256 uint256 pool = IERC20underlyingToken.balanceOfaddressthis; return pool.addoutstandingAmount; function removeFilledTradeAmountuint256 amt external onlyPair outstandingAmount = outstandingAmount.subamt; emit...

User rewards stop accruing after any _writeCheckpoint calling action

Lines of code Vulnerability details Any user balance affecting action, i.e. deposit, withdraw/withdrawToken or getReward, calls writeCheckpoint to update the balance records used for the earned reward estimation. The issue is that writeCheckpoint always sets false to voted flag for the each new...

Consistently check account balance before and after transfers for Fee-On-Transfer discrepancies

Lines of code Vulnerability details As arbitrary ERC20 tokens can be passed, the amount here should be calculated every time to take into consideration a possible fee-on-transfer or deflation. Also, it's a good practice for the future of the solution. Affected code:...

Aura.sol mint() function has a bug in the logic

Lines of code Vulnerability details Impact Intention is that during inflation period operator will or at least will be able to min EMISSIONSMAXSUPPLY token amount. Due to a logic bug amount of operator mintable tokens directly depends on how many tokens are minted by function minterMint and init...

ConvexMasterChef: When _lpToken is cvx, reward calculation is incorrect

Lines of code Vulnerability details Impact In the ConvexMasterChef contract, a new staking pool can be added using the add function. The staking token for the new pool is defined using the lpToken variable. However, there is no additional checking whether the lpToken is the same as the reward tok...

ConvexMasterChef: When _lpToken is duplicated, reward calculation is incorrect

Lines of code Vulnerability details Impact Same as IDX-002 in In the ConvexMasterChef contract, a new staking pool can be added using the add function. The staking token for the new pool is defined using the lpToken variable. However, there is no additional checking whether the lpToken is already...

[WP-H1] Debt can be repaid with a depegged underlyingToken, which can be exploited by arbitrageurs and drives the market price of alToken to match the worst depegged underlyingToken

Lines of code Vulnerability details function normalizeUnderlyingTokensToDebtaddress underlyingToken, uint256 amount internal view returns uint256 return amount underlyingTokensunderlyingToken.conversionFactor; function repayaddress underlyingToken, uint256 amount, address recipient external...

TransmuterBuffer's setAlchemist will freeze deposited funds

Lines of code Vulnerability details Currently setAlchemist doesn't check whether there are any open positions left with the old Alchemist before switching to the new one. As this require a number of checks the probability of operational mistake isn't low and it's prudent to introduce the main...

[LidoVault.sol][_withdrawFromYieldPool] Should not call return receivedETHAmount before the require check

Lines of code Vulnerability details Impact It is possible that users cannot receive ETH if sending ETH to users is not successful because the require check is unreachable. Proof of Concept withdrawFromYieldPool function executes the following code if user requests ETH withdrawal. if asset ==...

Race condition in exercising the options

Lines of code Vulnerability details Impact Option buyers might never exercise their options with a bad actor vault owner, hence creating trust issues to the platform since the promised functionality causes only loss of funds. Proof of Concept Alice creates a vault for her high valued NFT. Bob buy...

EthAssetManager and ThreePoolAssetManager don't control Meta tokens decimals

Lines of code Vulnerability details Both contracts treat meta assets as if they have fixed decimals of 18. Minting logic breaks when it's not the case. However, meta tokens decimals aren't controlled. If actual meta assets have any other decimals, minting slippage control logic of both contracts...

Admin has ability to rugpull all tokens

Lines of code Vulnerability details Impact Currently it is possible for the admin to pull all tokens belonging to the Gravity bridge. In normal circumstances this is probably fine, but if the admin account were compromised this would lead to the bridge being drained of locked funds. Furthermore, ...

In MerkleVesting.sol::withdraw check return value of ERC20 transfer or use safeTransfer of OZ

Lines of code Vulnerability details Impact MerkleVesting.solL173 tree.tokenBalance -= currentWithdrawal; IERC20tree.tokenAddress.transferdestination, currentWithdrawal; In case of failed transfer here it do not check return value of transfer. it updates the tree balance without transfering the...

Multiple vestings for the same user will fail

Lines of code Vulnerability details Impact Loss of funds from multiple vestings for a single user Proof of Concept In MerkleVesting and MerkleResistor vestings are distributed using merkle trees. Creators of the vesting submit the Merkle root of the tree and deposit the funds to be distributed. A...

FixedPricePassThruGate locks excess ETH payments

Lines of code Vulnerability details The FixedPricePassThruGate accepts ETH amounts greater than or equal to the calculated price, but only forwards an amount exactly equal to the calculated price to the configured beneficiary address. Excess ETH sent through the gate will be permanently locked in...

Consistently check account balance before and after transfers for Fee-On-Transfer discrepancies

Lines of code Vulnerability details Impact Wrong bookkeeping, albeit limited to the concerned tree with a FoT Token Wrong amount emitted Proof of Concept contracts/MerkleDropFactory.sol: 77: requireIERC20merkleTree.tokenAddress.transferFrommsg.sender, addressthis, value, "ERC20 transfer failed";...

CNft.sol - revert inside safeTransferFrom will break composability & standard behaviour

Lines of code Vulnerability details The function safeTransferFrom is a standard interface in ERC1155, and its expected to succeed if all the parametes are valid, and revert on error, which is not the case here so its a deviation. Refer to the EIP-1155 safeTransferFrom rules: MUST revert if to is...

amount requires to be updated to contract balance increase (12)

Lines of code Vulnerability details Impact Every time transferFrom or transfer function in ERC20 standard is called there is a possibility that underlying smart contract did not transfer the exact amount entered. It is required to find out contract balance increase/decrease after the transfer. Th...

Lack of validation on many important setters can lead to unwanted results

Lines of code Included below Vulnerability details Impact There are several important setter functions that lack validation on either the value itself or the timing on which the function can be called. It seems that the developer intentionally wrote these contracts with flexibility in mind, so I ...

Deprecated oracle can return 0 as a price

Lines of code Vulnerability details Impact According to Chainlink's documentation, the latestAnswer function is deprecated. Proof of Concept This function does not error if no answer has been reached but returns 0. Besides, the latestAnswer is reported with 18 decimals for crypto quotes but 8...

Dutch Auction fails when maxDaSupply is not reached

Lines of code Vulnerability details Impact Dutch Auction fails when maxDaSupply is not reached Proof of Concept Dutch Auction should update finalPrice every time price decreases. However, currently fianlPrice is updated only when auction reaches full supply reserved for auction phase. 1. Alice bu...

Users can use updateBoost function to claim unfairly large rewards from liquidity mining contracts for themselves at cost of other users.

Lines of code Vulnerability details Impact Users aware of this vulnerability could effectively steal a portion of liquidity mining rewards from honest users. Affected contracts are: SupplyMinerV2, DemandMinerV2, PARMinerV2 VotingMinerV2 is less affected because locking veMIMO in votingEscrow...

ABDKMath64 performs multiplication on results of division

Lines of code Vulnerability details Impact Solidity could truncate the results, performing multiplication before division will prevent rounding/truncation in solidity math. Recommended Mitigation Steps Consider ordering multiplication first. --- The text was updated successfully, but these errors...

ERC20 tokens with no return value will fail to transfer

Lines of code Vulnerability details Although the ERC20 standard suggests that a transfer should return true on success, many tokens are non-compliant in this regard including high profile, like USDT . In that case, the .transfer call here will revert even if the transfer is successful, because...

claimRewards() didnt follow the safe check effect pattern

Judge @GalloDaSballo has assessed the 2nd item in QA Report 230 as Medium risk. The relevant finding follows: … Impact a user can claim a reward by calling the claimRewards, however this function didnt follow the correct check effect pattern, where the zero address is set after making an external...

withdrawFees() function shoud require to address to not be zero

Lines of code Vulnerability details Impact withdrawFees don't check that to address is not zero and send fee to the address without any check that confirms admin has set the address. bentoBox don't accept transferring to zero address, otherwise this could be high risk Proof of Concept As you can...

Potential Sandwich Attack: Arbitrage bots can front run reward tokens being sent to the liquidity mining contracts

Lines of code Vulnerability details Impact For the PARMiner and DemandMiner contracts, arbitrage bots could harvest significant portion of rewards by monitoring MEV, and front run any reward token either a.mimo or par being transferred to the liquidityMining contract i.e. call the deposit functio...

Oracle data feeds are insufficiently validated

Lines of code Vulnerability details Impact If the oracle price feeds are insufficiently validated, there will be pricing errors leading to the miss-pricing of assets/risk Proof of Concept The code does not verify that answeredInRound = roundID for both cases where an oracle is used, and the...

RoleManager.sol: _revokeRole doesn't remove from the _roleMembers[role] set

Lines of code Vulnerability details Impact In the file RoleManager.sol the function revokeRole doesn't remove the account from the roleMembersrole set. This makes getRoleMemberCount wrong for the else part therefore the renounceGovernance require, on the number of governor, useless and risky as...

_revokeRole doesn't remove account from roleMember set

Lines of code Vulnerability details Impact The function doesn't remove the address from roleMembersrole set, which will mess up with the roleCount Proof of Concept Tools Used Recommended Mitigation Steps rolesrole.membersaccount = false; roleMembersrole.removeaccount; --- The text was updated...

Swapper3Crv's swapping path can be suboptimal

Lines of code Vulnerability details Impact Swapper3Crv.swap result can be suboptimal as only paths with ETH are evaluated. Setting severity to medium as despite function availability not affected there can be some fund losses as a result. Proof of Concept tokenAmountOut uses fixed tokenIn, ETH,...

Unchecked parameters in Chainlink latestRounddata() could lead to retrieve stale data

Lines of code Vulnerability details Impact Oracle can retrieve unchecked stale data Proof of Concept In ChainlinkpriceOracle.sol the function function refreshedAssetPerBaseInUQaddress asset public override returns uint AssetInfo storage assetInfo = assetInfoOfasset; , int basePrice, , , =...

Missing Validations for the return values of Chainlink Price feeds

Lines of code Vulnerability details Impact You check only the answerThe price after calling the chainlink Chainlink Price feeds in the following lines. In addition, you need to check whether the data is really updated. Proof of Concept Tools Used code review Recommended Mitigation Steps Please ad...

Should check return data from chainlink aggregators

Lines of code Vulnerability details Impact The refreshedAssetPerBaseInUQ function in the contract ChainlinkPriceOracle.sol fetches the asset price from a Chainlink aggregator using the latestRoundData function. However, there are no checks on roundID nor timeStamp, resulting in stale prices. The...

JPEGLock.lockFor can relock for specific nft, which overwrites previous lock and cause JPEG loss of the locker

Lines of code Vulnerability details Impact NFTVault contract allows anyone to finalize a pending NFT value proposal by calling the finalizePendingNFTValueETH function. A finalizer must lock an equivalent amount of JPEG tokens to the proposed NFT value in JPEGLock, and can only withdraw those toke...

FungibleAssetVaultForDAO: Use latestRoundData + validate data freshness

Lines of code Vulnerability details Details & Impact The deprecated latestAnswer API is being used, which may at any time fail to work if Chainlink ends support for it. In addition, the data freshness should be checked. The oracle could, for example, not have been updated in a while, causing...

yVault: First depositor can break minting of shares

Lines of code Vulnerability details Details The attack vector and impact is the same as TOB-YEARN-003, where users may not receive shares in exchange for their deposits if the total asset amount has been manipulated through a large “donation”. Proof of Concept Attacker deposits 1 wei to mint 1...

Not calling approve(0) before setting a new approval causes the call to revert when used with Tether (USDT)

Lines of code Vulnerability details Some tokens do not implement the ERC20 standard properly but are still accepted by most code that accepts ERC20 tokens. For example Tether USDT's approve function will revert if the current approval is not zero, to protect against front-running changes of...

Malicious users can frontrun borrowers trying to repay loans, causing DoS and possibly a loan default

Lines of code Vulnerability details Impact Attackers can listen for a borrower to call repayAndCloseLoan on a specific loanId, and frontrun their transaction with a call to lend, creating a new loan with an increased amount, causing the borrower's transaction to fail due to the new loanAmount bei...

Lender can stop others from offering higher rates.

Lines of code NFTLoandFacilitator.lend; L205 Vulnerability details Impact A lender using an upgradeable smart contract could stop other lenders from buying him out, essentially causing a DoS. Proof of Concept Lender uses an upgradeable smart contract that front runs competing lenders and upgrades...

Malicious owner can steal some funds from borrower

Lines of code Vulnerability details Impact Owner can make changes to the protocol with immediate effect. Malicious owner can watch for big lend in the mempool and front run it by maxing out originationFeeRate to 5%. The users, both lender and borrower, will still think that originationFeeRate is...

Code credits fee-on-transfer tokens for amount stated, not amount transferred

Lines of code Vulnerability details Some ERC20 tokens, such as Tether USDT, allow for charging a fee any time transfer or transferFrom is called. Impact The code miscalculates whether the loan has been fully paid or bought out because it relies on the value of amounts passed in rather than the...

Unauthorized ERC20 changes

Lines of code Vulnerability details Impact It's possible by anyone to change the name and symbol of CToken. Proof of Concept The require was made in reverse condition, it checks that the sender must be different than admin in order to be able to change the name and symbol requiremsg.sender !=...

Tokens with fee on transfer are not supported

Lines of code Vulnerability details There are ERC20 tokens that charge fee for every transfer / transferFrom. Vault.soladdValue assumes that the received amount is the same as the transfer amount, and uses it to calculate attributions, balance amounts, etc. But, the actual transferred amount can ...

Use .call instead of .transfer for increased security

Lines of code Vulnerability details Impact The issue highlighted here will reduce gas costs and avoid hacks Proof of Concept The .transfer function at the following places can be replaced with .call as the former has a hard dependency on gas costs as it forwards a fixed amount of gas: 2300. For...

Past state query results are susceptible to manipulation due to multiple states with same block number

Lines of code https://github.com/code-423n4/2022-0...

Not handling return value of transferFrom command can create inconsistency

Lines of code Vulnerability details The below transferFrom command is called at two places in the core contracts, followed by an emit event payableToken.transferFrommsg.sender,recipient,amount emit ......; The return value is not checked during the payableToken.transferFrom Impact In the event of...

STORAGE COLLISION BETWEEN PROXY AND IMPLEMENTATION (LACK EIP 1967)

Lines of code Vulnerability details Impact Storage collision because of lack of EIP1967 could cause conflicts and override sensible variables Proof of Concept contract CoreProxy is Ownable address private immutable implement; When you implement proxies, logic and implementation share the same...