Anyone can add Gauge reward tokens and cause DoS

Lines of code Vulnerability details Impact The Gauge.notifyRewardAmount function does not have any access restriction. Anyone an attacker can frontrun and call this function to add arbitrary even malicious gauge reward tokens up to MAXREWARDTOKENS = 16. An attacker is able to frontrun and add 16...

Anyone can add Bribe reward tokens and cause DoS

Lines of code Vulnerability details Impact The Bribe.notifyRewardAmount function does not have any access restriction. Anyone an attacker can frontrun and call this function to add arbitrary even malicious reward tokens up to MAXREWARDTOKENS = 16. An attacker is able to frontrun and add 16 fake...

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: contracts/contracts/Bribe.sol:...

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...

ExtraRewardsDistributor deposits don’t work with fee-on transfer tokens

Lines of code Vulnerability details Impact There are ERC20 tokens that may make certain customizations to their ERC20 contracts. One type of these tokens is deflationary tokens that charge a certain fee for every safetransfer or safetransferFrom . Proof of Concept The ExtraRewardsDistributor’s...

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:...

Griefing attack by transferring aTokens to the contract

Originally part of a QA report by Tadashi 69 Griefing attack by transferring aTokens to the contract Summary: tokenToShares uses the following formula for computing the total shares of an user: return supply == 0 ? tokens : tokens.mulsupply.divaToken.balanceOfaddressthis; An attacker wishing to...

Possible lost msg.value

Lines of code Vulnerability details Impact Possible lost value in depositCollateral function call Proof of Concept In call depositCollateral can will send value and the asset can be an ERC20!= address0, if LidoVault and ConvexCurveLPVault contract receive this call the fouds will lost Also in...

YearnTokenAdapter's wrap can become stuck as it uses one step approval for an arbitrary underlying

Lines of code Vulnerability details Some tokens do not allow for approval of positive amount when allowance is positive already to handle approval race condition, most known example is USDT. This can cause the function to stuck whenever a combination of such a token and leftover approval be met...

ConvexCurveLPVault's _transferYield can become stuck with zero reward transfer

Lines of code Vulnerability details Now there are no checks for the amounts to be transferred via transferYield and processTreasury. As reward token list is external and an arbitrary token can end up there, in the case when such token doesn't allow for zero amount transfers, the reward retrieval...

Cally does not support ERC20 tokens with built-in fee

Lines of code Vulnerability details Impact Contract Cally does not properly handle ERC20 tokens that charge fee on their transfers. Implementation of such a tokens does not transfer exact amount provided to transfer but part of it is charged as a fee, burned or used in some other way. This leads ...

“No Revert on Failure“ tokens can be stolen from the contract by disguising them as NFTs.

Lines of code Vulnerability details Impact If a user creates a vault with an ERC20 token with the following two properties: 1. There’s a way to make transferFrom fail to transfer tokens without reverting e.g. some tokens like ZRX return false on failure instead of reverting. 2. fransferFromfrom,...

Use ERC721.safertransferFrom instead of ERC721.transferFrom when you send out NFT

Lines of code Vulnerability details Impact Buyers can accidentally lose their NFT if they send to incorrect address. Proof of Concept When the buyer decide to call exercise the NFT is transfered using transferFrom. This is risky because if the destination msg.sender is a contract and it is unable...

TokenType mismatch with true type can be exploited to steal funds

Lines of code Vulnerability details A vault can be created for different TokenTypes, namely ERC20 and ERC721. These tokens have different logic, so a user needs to pass the type of the underlying token when creating a vault. At the end of createVault the user's tokens are pulled into the contract...

Fee-on-transfer / rebasing ERC20 cannot be used as underlying

Lines of code Vulnerability details Some ERC20 tokens may have fee-on-transfer or change balance without owner intervention. If these tokens are used as underlying in the protocol they can be lost. Proof of concept Alice creates a vault with a token that has a 1% fee on transfer. She sends...

[WP-H0] Fake balances can be created for not-yet-existing ERC20 tokens, which allows attackers to set traps to steal funds from future users

Lines of code Vulnerability details function createVault uint256 tokenIdOrAmount, address token, ... external returns uint256 vaultId ... Vault memory vault = Vault ... ; // vault index should always be odd vaultIndex += 2; vaultId = vaultIndex; vaultsvaultId = vault; // give msg.sender vault tok...

Payble function allows for Eth transfer even when ERC20 tokens are being used

Lines of code Vulnerability details Impact The function depositCollateral in GeneralVault.sol is payable. This needs to be payable for the case in LidoVault where depositToYeild expects ETH to be transferred. However for the ConvexCurveLPVault.sol and the case when LidoVault is not using Eth as a...

no-revert-on-transfer ERC20 tokens can be drained

Lines of code Vulnerability details Impact Some ERC20 tokens don't throw but just return false when a transfer fails. This can be abused to trick the createVault function to initialize the vault without providing any tokens. A good example of such a token is ZRX: Etherscan code When such a vault ...

Malicious ERC20 or ERC777 could be used as collateral

Lines of code Cally.solL296 Vulnerability details Impact A malicious ERC20 or ERC777 could be used as collateral and rug the exerciser on exercise through a malicious implementation of ERC20vault.token.safeTransfer. Proof of Concept Any ERC20/ERC777 token is accepted as there is no whitelist. Thi...

createVault() does not verify ERC20 token contract exists before transferring

Lines of code Vulnerability details Impact There are no checks to ensure the the vault.token contract exists when creating a vault. Token address are deterministic in the EVM and can be known ahead of time. As a result it is possible for a user to call createVault with token set to a ERC20 contra...