[PNM-005] Reentrancy of function sell

Lines of code Vulnerability details Description In function chargeFee, a potential reetrancy can be triggered by the factory. Since function sell invokes chargeFee in the middle of its function body, it potentially impacts the calculation, e.g., the totalSupply would be incorrect since the tokens...

_secondaryReserveRatio is likely to be overflowed due to an unsafe downcast

Lines of code Vulnerability details msg.value SCALE 1e18 / initialTokenSupply initialTokenPrice is likely to be more than maxuint32, and therefore secondaryReserveRatio can be overflowed due to the unsafe downcast to uint32. For example, for: initialTokenSupply = 1e20. initialTokenPrice = 1e14. T...

Discrepancies between document and code implementation

Lines of code Vulnerability details Impact This will tarnish the credibility of the system. Proof of Concept Document says buyout time as 3 days. But the code is implemented with 5 days as buyout time. Tools Used Manual verification Recommended Mitigation Steps Implement the code as per what...

Ineffective TWAV Implementation

Lines of code Vulnerability details Background The current TWAV implementation consists of an array of 4 observations/valuations called twavObservations. Whenever, the new valuation is updated, the new cumulative valuation will be appended to the twavObservations array and the oldest...

DoS with block gas limit--External calls inside a loop might lead to a denial-of-service attack.

Lines of code Vulnerability details Impact --Check: calls-loop --Severity: Medium --Confidence: Medium External calls can fail accidentally or deliberately, which can cause a DoS condition in the contract. Proof of Concept -- --ConsenSys Smart Contract Best Practices -- -- Tools Used...

REENTRANCY-Avoid transfer() as reentrancy mitigations. Transfer do not protect from reentrancies in case of gas price changes.

Lines of code Vulnerability details Impact --Check: reentrancy-unlimited-gas --Severity: Informational --Confidence: Medium Transfer and send have been recommended as a security best-practice to prevent reentrancy attacks because they only forward 2300 gas. That being said, gas repricing of...

Malicious Basket Could Be Used To Rug Fractionalized Token Holders

Lines of code Vulnerability details Proof-of-Concept The NibblVaultFactory.createVault accepts any NFT address or any Basket address. Therefore, an attacker could pass a malicious basket address during vault creation. function createVault address assetAddress, address curator, string memory name,...

sell() and buy() should not have whenNotPaused modifier

Lines of code Vulnerability details Impact Impacts are two fold: 1. admin should not be allowed to stop users from selling/cashing out their assets under any circumstance. 2. Due to poor timing or malicious admin activity, it could be the case that buy is put on pause right after initiateBuyout i...

attacker can give a smaller amount of tokens and not pay the fees

Lines of code Vulnerability details Impact an attacker can specify an amount like from 1 wei or more but depends on the state of the contract variables. amount= 1 adminfee=5 / 1000000 = 0 because of persion loss whichfeeAdmin=0 same thing for the other fees and there is no check that they cant be...

Malicious NFT

Lines of code Vulnerability details Impact Anybody can create a vault which fractionalizes their NFT. However, this process should go through a whitelist and review process because a maliciously implemented NFT contracts can reclaim ownership of the contract despite it technically being 'owned' b...

Buys/sells will be front-run by MEV bots

Lines of code Vulnerability details Impact Since the value of the vault depends on the Bancor formula, it's important that transactions can't be front-run, because doing so, even for small amounts, will change the valuation price for subsequent buys/sells. The link the sponsor provided describes...

Buy logic is not correct

Lines of code Vulnerability details Impact This will affect the curves from where the buy need to happen. This will lead to erroneous result. Proof of Concept Tools Used Manual calculation and code review Recommended Mitigation Steps Update the Buy logic by referring the sell logic. --- The text...

Upgraded Q -> H from 285 [1655952312863]

Judge has assessed an item in Issue 285 as High risk. The relevant finding follows: 1. Excess ether sent to FixedPricePassThruGate is lost low passThruGate redirects to a beneficiary only gate.ethCost, requiring that msg.value = gate.ethCost. As there are no other ways to access native tokens hel...

Upgraded Q -> H from 94 [1655957384739]

Judge has assessed an item in Issue 94 as High risk. The relevant finding follows: 2. Return values of transfer/transferFrom not checked Not all IERC20 implementations revert when there's a failure in transfer/transferFrom. The function signature has a boolean return value and they indicate error...

missed valid address check for assetAddress

Lines of code Vulnerability details Impact Malicious Actor can do DoS using Reentrance using createVault and can create vault without depositing any asset Proof of Concept pragma solidity ^0.8.10; import "./NibblVaultFactory.sol"; contract ERC721Attack address curator =...

initiateBuyout and sell functions on NibbleVault.sol Reentrancy vulnerability

Lines of code Vulnerability details Impact 1. In NibbleVault.sol, it is possible for a contract to prevent the Sell event from being fired after being sent ether. From calling the sell function on line 390, an attacker contract is able to keep the event hidden from being listened to by stopping t...

whenNotPaused modifier missing

Lines of code Vulnerability details Impact whenNotPaused modifier is missing in both createBasket function NibblVaultFactory.solL80 and withdrawUnsettledBids function NibblVault.solL424 This means even when contract is in paused state this function will still be operational Note Other impacted...

ERC1155 support unchecked - NFT can be lost

Lines of code Vulnerability details Impact It is not checked whether withdrawn token supports ERC1155 interface. Also there is no check to see if necessary approval have been set for sending nft The fix need to be applied for all other functions withdrawing ERC1155 Proof of Concept 1. Observe the...

Transition notBoughtOut -> boughtOut -> notBoughtOut possible because of updateTWAV

Lines of code Vulnerability details Impact Because rejectBuyout uses the TWAV, which is time-weighted and updateTWAV can be called, it is possible that notBoughtOut is true at first, then boughtOut is true, and then notBoughtOut is true again. See Proof of Concept for how one can construct such a...

ERC721 support not checked - NFT loss

Lines of code Vulnerability details Impact It is not checked whether withdrawn token supports ERC721 interface. Also there is no check to see if necessary approval have been set for sending nft The fix need to be applied for all other functions withdrawing ERC721 Proof of Concept 1. Observe the...

use ECDSA helper library instead of ecrecover

Lines of code Vulnerability details use ECDSA helper library instead of ecrecover the function permit adds approval for a spender for a certain amount of value use of ecrecover to validate signatures without a nonce will allow signatures to be replayed to add additional approvals due to signature...

Some users can redeem more reserve tokens after curator redeems accumulated curator fee.

Lines of code Vulnerability details Impact It is possible for some users to redeem more reserved tokens if the curator redeems accummulated curator fee before their redeem action in the case of a boughtOut. This is possible because NibblVault.redeemCuratorFee sets feeAccruedCurator back to 0. So ...

No checks for the input of borrow cap

Lines of code Vulnerability details Impact due to lack of input validation of borrowcap , it can be borrowcap for a ctoken can be 0 and value of 0 corresponds to unlimited borrowing Proof of Concept Tools Used manual reveiw Recommended Mitigation Steps add input validation while using it in loop...

Attacker can frontrun calling _mint_to_Accountant() which mints the entire supply to the caller, and sets them as _accountant and admin

Lines of code Vulnerability details Impact By leaving minttoAccountant with no access control when accountant = address0 it allows an attacker to call the function, mint the entire supply to themselves, and gain the accountant and admin roles. Additionally, the parameter "address...

Overprivileged admin can grant unlimited WETH

Lines of code Vulnerability details Impact Admin can grantComp to any address using any amount and drain the contract. Proof of Concept If admin key gets compromised there is no timelock, no amount boundaries and no address limitations to prevent the assets to be drained immediately to the...

CNote updates the accounts after sending the funds, allowing for reentrancy

Lines of code Vulnerability details Having no reentrancy control and updating the records after external interactions allows for funds draining by reentrancy. Setting the severity to medium as this is conditional to transfer flow control introduction on future upgrades, but the impact is up to th...

first user can steal everyone else's tokens

Lines of code Vulnerability details Impact Detailed description of the impact of this finding. A user who joins the systems first stakes first can steal everybody's tokens by sending tokens to the system externally. This attack is possible because you enable staking a small amount of tokens. Proo...

Redeem function can silently fail

Lines of code Vulnerability details Impact During the code review, It has been observed that return value of redeem function is not checked. Redeem operation can silently fail and the protocol can expect It is successfully executed. From compound, the comment can be seen from below. CErc20 / CEth...

repayAmountFinal is not considered while calculating actualRepayAmount while calling doTransferIn(payer, repayAmount)

Lines of code Vulnerability details Impact repayAmountFinal is not used inside repayBorrowFresh The computation for actualRepayAmount doesnot account for repayAmountFinal in L111. Proof of Concept function repayBorrowFreshaddress payer, address borrower, uint repayAmount internal override...

WETH.totalSupply() returns wrong result.

Lines of code Vulnerability details Impact WETH.totalSupply returns wrong result. I can't find other contracts that use this function but WETH.sol is a base contract and it should be fixed properly. Proof of Concept WETH.balanceOf just returns a balance of a specific address and totalSupply must ...

Missing zero address check can set treasury to zero address

Lines of code Vulnerability details Impact AccountantDelegate.initialize is missing a zero address check for treasury parameter, which could may allow treasury to be mistakenly set to 0 address. Proof of Concept Tools Used Manual review Recommended Mitigation Steps Add a require check for zero...

Attacker can steal all tokens from pools

Lines of code Vulnerability details Attacker can steal all tokens from pool 2 issues 1.On deployment totalsupply is zero and reserve0 and reserve1 is zero called minting 103 to address zero And if tokens have supply in them amount0=1018 amount1=1018 liquidity= sqr1e36 - 103 =1015 which is still...

Queued proposals cannot be executed in GovernorBravoDelegate.sol

Lines of code GovernorBravoDelegate.solL63 Vulnerability details Impact In GovernorBravoDelegate.sol's queue function, the executed value for the proposal to be queued is set to true. The execute function in GovernorBravoDelegate.sol will revert when called since the state of the proposal is...

WETH.sol computes the wrong totalSupply()

Lines of code Vulnerability details Impact Affected code: WETH.sol is almost copied from the infamous WETH contract that lives in mainnet. This contract is supposed to receive the native currency of the blockchain for example ETH and wrap it into a tokenized, ERC-20 form. This contract computes t...

Oracle may be attacked if an attacker can pump the tokens for the entire block

Lines of code Vulnerability details Impact Attacker may use huge amount of their fund to pump the token in a liquidity pair for one entire block. The oracle will capture the manipulated price as current TWAP implementation may only cover 1 block if timed correctly. First block on every periodSize...

MasterChef's emergencyWithdraw can be reentered drawing all lptokens from the contract if pool.lpToken allows for transfer flow control

Lines of code Vulnerability details User's LP funds accounting update in emergencyWithdraw happens after lpToken transfer. If pool.lpToken allows for the control of transfer call flow or can be upgraded to allow it in the future i.e. beforetokentransfer, afterTokenTransfer type of hooks, or an...

getWETHAddress() returns wrong address

Lines of code Vulnerability details Impact The hardcoded return value is the address of COMP token in mainnet not of WETH in getWETHAddress. grantCompInternal function depends on this return value which will cause unintended issues. Proof of Concept function grantCompInternaladdress user, uint...

Base rate update frequency can be bypassed by an admin

Lines of code Vulnerability details Impact Base rate update frequency can be bypassed by an admin. Above function require updateFrequency blocks to be passed. Proof of Concept function updateBaseRateuint newBaseRatePerYear public // check the current block number uint blockNumber = block.number;...

newblockchain report: Missing access control in Proposal-Store.sol

Lines of code Vulnerability details Impact Anyone can add proposal. These proposals are used later to be executed by timelock in GovernorBravoDelegate. However, it is unclear whether the code works as intended: see the QA report "Upon queue executed true in GovernorBravoDelegate". Possible...

Transferring any amount of the underlying token to the CNote contract will make the contract functions unusable

Lines of code Vulnerability details Impact The contract expects the balance of the underlying token to == 0 at all points when calling the contract functions by requiring getCashPrior == 0, which checks token.balanceOfaddressthis where token is the underlying asset. An attacker can transfer any...

CNote balance can be affected by griefing attack

Lines of code Vulnerability details Functions borrowFresh, repayBorrowFresh, mintFresh, redeemFresh require CNote balance to be strictly zero, reverting unconditionally otherwise. However, as CNote is ERC20 with usual transfer functionality, anyone can send a cNote tokens to the contract itself,...

Note: When _initialSupply ! = 0, the _mint_to_Accountant function will fail

Lines of code Vulnerability details Impact In Note contract, if initialSupply ! = 0, totalSupply will overflow when the minttoAccountant function executes mintmsg.sender, typeuint.max constructorstring memory name, string memory symbol, uint256 totalSupply public name = name; symbol = symbol;...

getCashPrior == 0 not checked at the end of redeemFresh

Lines of code CNote.solL332 Vulnerability details Impact To ensure that there are no Note tokens in CNote.sol the getCashPrior value should be exactly 0 at the end of every function that transfers tokens in and out of the contract. In the redeemFresh function, the getCashPior value is not checked...

In Cnote.sol, anyone can initially become both accountant and admin

Lines of code Vulnerability details Impact Affected code: The function setAccountantContract is supposed to be called after contract initialization, so that the accountant is immediately set. However, this function completely lacks any access control it’s just public so an attacker can monitor th...

CNote: Attacker can frontrun the calling of _setAccountantContract and gain admin priviledges and insert a malicious accountant contract

Lines of code Vulnerability details Impact The function does not have access control before the accountant address is set, allowing anyone to call the function, gain admin privileges, and set the accountant address. Proof of Concept CNote.solL17 Recommended Mitigation Steps Include access control...

Incorrect repayAmount used in CNote

Lines of code Vulnerability details Impact repayAmount was used instead of repayAmountFinal in CNote.repayBorrowFresh. This will lead to revert if the borrower want to repay full amount with typeuint.max Proof of Concept uint actualRepayAmount = doTransferInpayer, repayAmount; Recommended...

newProposal.executed automatically set to true

Lines of code Vulnerability details Impact Proposals might be falsely deemed as executed when in fact they have not been executed yet. Proof of Concept The queue function sets newProposal.executed = true even though that is not technically true. For the proposal to be executed it needs to be call...

Block.timestamp is always growing in epoch seconds and observation.timestamp needs to be called is its very unlikely to for it to be equal each other Bypassing

Lines of code Vulnerability details Block.timestamp is always growing in epoch seconds and observation.timestamp needs to be called is its very unlikely to for it to be equal each other Bypassing observation and gets it to be wrong length which could cause logic brakes and worse because your not...

BaseRate can be update by anyone

Lines of code Vulnerability details Impact There is no access modifier in updateBaseRate due to which, anyone can change Baserate to a very low value an borrow the large value function updateBaseRateuint newBaseRatePerYear public Proof of Concept Tools Used manual review Recommended Mitigation...

Functions in CNote.sol are internal instead of external/public

Lines of code Vulnerability details Impact Most of the functions in CNote.sol are internal mutability and have no other locations they are being called. This renders most of the functionalities in the contract to be uncallable. Tools Used Manual review Recommended Mitigation Steps Change to the...