When liquidation is not locked, anyone can liquidate another persons' collateral

Lines of code Vulnerability details Impact Petty users can liquidate other people's NFT immediately when the liquidation threshold is reached. Proof of Concept The owner controls the function setLiquidationsLocked and calls the function when a collateral needs to be liquidated function...

PUNK does not conform to ERC721 standard hence safeTransferFrom from solmate does not work

Lines of code Vulnerability details Impact Since protocol's intended NFT target is PUNK currently, the protocol will be hugely affected. Proof of Concept Attempts to transfer the NFT is done in 2 places. 1. removeCollateral 2. purchaseNFT Firstly, this means that once a collateral is added to the...

Faulty fee handling in buyAndReduceDebt

Lines of code Vulnerability details Impact When passing fee params to buyAndReduceDebt with swapFeeTo and swapFeeBips, the PaprController will try to send the underlying token on the following line: underlying.transferparams.swapFeeTo, amountIn params.swapFeeBips / BIPSONE; But in a normal state,...

Early NFT collections such as CryptoPunks and MoonCats can not be used as a collateral

Lines of code Vulnerability details Impact Early NFT collections such as CryptoPunks, EtherRocks and MoonCats are not compliant with ERC721 standard. therefore, they can not be used as a collateral since transferring will fail. I beleive it would be a huge advantage for the protocol to support su...

Underlying With Non-Standard Decimals Not Supported

Lines of code Vulnerability details Impact Arithmetic operations are performed with the assumption that the token always has 18 decimals. Proof of Concept It would not be possible without using 18 decimal places of the base capital. Tools Used vscode Recommended Mitigation Steps Consider whether...

Potential DOS in removeCollateral

Lines of code Vulnerability details Impact Function removeCollateral may fail under certain circumstances, potentially causing DOS to user trying to withdraw their collateral asset. This action may be time critical and may cause the user to lose funds due to price change etc. Proof of Concept Cal...

function underwritePriceForCollateral() uses message.timestamp > block.timestamp to validate oracle message timestamp but it can create MEV as miners can control block.timestamp and revert some of the user's transactions

Lines of code Vulnerability details Impact Function underwritePriceForCollateral validates the oracle message which includes the price of the NFT and returns the price of an asset from a signed oracle message. to check the validity of the message's timestamp code checks that if...

Initial value of auction starter discount is set wrong

Lines of code Vulnerability details Impact The protocol offers a discount for auction starters when purchasing the liquidated NFT as an incentive for users to start an auction. I believe the intended discount should be 10%, but is currently implemented at 90%. 90% is too massive a discount for th...

Signature mallebaility in underwritePriceForCollateral

Lines of code Vulnerability details Impact underwritePriceForCollateral has signature malleability as it doesn't check for a returned address of not 0. Value can be set to 0 oracleSigner Proof of Concept function underwritePriceForCollateralERC721 asset, PriceKind priceKind, OracleInfo memory...

PaprController is vulnerable to reentrancy attacks

Lines of code Vulnerability details Impact Malicious users can steal PAPR tokens through reentrancy attacks. Proof of Concept Function PaprController.purchaseLiquidationAuctionNFT may trigger a reentrancy becase it calls ERC721.safeTransferFrom in NFTEDA.purchaseNFT:...

mintlistMint: Address that is in both merkle trees not correctly handled

Lines of code Vulnerability details Impact It is possible to set two merkle roots for the mintlist mintlistMerkleRoot1 and mintlistMerkleRoot2 and both trees are used in queries: require MerkleProof.verifymerkleProof, mintlistMerkleRoot1, leaf || MerkleProof.verifymerkleProof, mintlistMerkleRoot2...

Borrowers don’t need to run the risk of being liquidated

Lines of code Vulnerability details Impact Borrowers are able to borrow Papr, swap it for another asset in Uniswap without ever having to pay their debt because they can remove their collateral without paying their debt. Ultimately leading to free assets at the cost of others. Proof of Concept As...

Liquidations force users into bigger debts

Lines of code Vulnerability details Impact User's uncovered debt increases when auction starts on their collateral token. The increased debt may be too big for a user and they might not be able to repay it, which forces them to wait for the auctioned token to be sold and accrue more debt due to t...

A BETTER APPROACH TO REVERTING CODE LINES ON _ADDCOLLATERALTOVAULT() AND _REMOVECOLLATERAL()

Lines of code Vulnerability details Impact In PaperControl.sol, callers would have to deal with function pre-maturely reverting upon encountering an element in collateralArr failing to pass the if statement in the function logic of addCollateralToVault and removeCollateral. The amount of gas wast...

Operator can buy papr with PaprController as the debtor.

Lines of code Vulnerability details Impact This requires that an NFT is in auction. When an operator calls purchaseLiquidationAuctionNFT the price variable is determined by a call to purchaseNFTAndUpdateVaultIfNeeded which calls purchaseNFT which calls safeTransferFrom on the auctionAssetContract...

Reentrancy attack allows to get loan for free

Lines of code Vulnerability details Impact Reentrancy attack allows to get loan for free when startLiquidationAuction is called on last collateral token. Proof of Concept When user has a bad debt, then anyone can start auction for his nft. To purchase token, liquidator can call...

function buyAndReduceDebt() spend more underlying token than user specified and also code doesn't check that swapFeeBips is less than BIPS_ONE and user can lose some of his underlying token balance that he gave protocol spending approval

Lines of code Vulnerability details Impact user can specify fee recipient and fee amount to send to that recipient and it is calculated by amount swapFeeBips / BIPSONE but there is no check in the code to make sure swapFeeBips is less than BIPSONE and if user set wrong value by mistake or client...

Start an auction without an NFT

Lines of code Vulnerability details Impact Requires that the account being liquidated has more than one NFT in PaprController. When an operator calls purchaseLiquidationAuctionNFT the price variable is determined by a call to purchaseNFTAndUpdateVaultIfNeeded which calls purchaseNFT which calls...

Oracle may return a stale price that is not resistant to flash crashes

Lines of code Vulnerability details Impact Oracle may return a stale price in the event of a flash crash which will affect protocol calculation of maxDebt and affect protocol. Proof of Concept Protocol uses the time weighted average pricing of 30 days to check the price of the NFT. uint256 consta...

Wrong implemention of ERC721TokenReceiver interface leads to incorrect collateral ownership and NFT loss

Lines of code Vulnerability details Impact To add a collateral, one could send the NFT directly to the contract, onERC721Received is called then to handle adding the collateral to the vault. However, if the user sends the NFT via an operator then the ownership of the collateral will be assigned t...

code doesn't check that To address is not 0x0 in contract function, if user call contract's function with wrong value he would lose his funds

Lines of code Vulnerability details Impact There is no sanity checks when user wants to get loan or ... for a to address and if the value of to set as 0 user would lose those funds. Proof of Concept none of the functions increaseDebtAndSellmintTo, , increaseDebtmintTo, ,...

Users may be liquidated right after taking maximal debt

Lines of code Vulnerability details Impact Since there's no gap between the maximal LTV and the liquidation LTV, user positions may be liquidated as soon as maximal debt is taken, without leaving room for collateral and Papr token prices fluctuations. Users have no chance to add more collateral o...

Upgraded Q -> M from #27 [1671522165760]

Judge has assessed an item in Issue 27 as M risk. The relevant finding follows: Dup of 45. The effect is severe enough IMO to warrant a med severity although I initially intepreted it as a spec mismatch. --- The text was updated successfully, but these errors were encountered: All reactions...

Stealing fund by applying reentrancy attack on removeCollateral, startLiquidationAuction, and purchaseLiquidationAuctionNFT

Lines of code Vulnerability details Impact By applying reentrancy attack involving the functions removeCollateral, startLiquidationAuction, and purchaseLiquidationAuctionNFT, an Attacker can steal large amount of fund. Proof of Concept Bob a malicious user deploys a contract to apply the attack...

Insufficient Timestamp Validation for Signed Messages

Lines of code Vulnerability details Impact A message can be signed by the oracle for any future point in time, and it will be valid for 20 minutes. If messages with invalid timestamps pointing to the future get signed, there is no way of invalidating them. A compromised or malfunctioning oracle...

Borrowers may earn auction proceeds without filling the debt shortfall

Lines of code Vulnerability details Impact The proceeds from the collateral auctions will not be used to fill the debt shortfall, but be transferred directly to the borrower. Proof of Concept Assume N is an allowed NFT, B is a borrower, the vault V is vaultInfoBN: 1. B add two NFTsN-1 and N-2 as...

Upgraded Q -> M from #22 [1671528533640]

Judge has assessed an item in Issue 22 as M risk. The relevant finding follows: NC-2 Return values of approve not checked --- The text was updated successfully, but these errors were encountered: All reactions...

The patch is not sufficient: there is another insidious exploit that can cause the same critical consequences

Lines of code Vulnerability details Status Has been reported to and confirmed by Jeff ENS team Note to the Judge I am not sure whether I should label this as a newly-identified High or a mitigation hard error. The root cause of this issue seems as same as the original report, but this requires us...

Upgraded Q -> M from #4 [1671527898955]

Judge has assessed an item in Issue 4 as M risk. The relevant finding follows: GroupBuy.contribute does not set pendingBalances for unused capital, leading to locked up money --- The text was updated successfully, but these errors were encountered: All reactions...

Upgraded Q -> M from #22 [1671528877220]

Judge has assessed an item in Issue 22 as M risk. The relevant finding follows: minBidPrices is rounded down --- The text was updated successfully, but these errors were encountered: All reactions...

setFundingPeriod leads to Price control

Lines of code Vulnerability details Impact Attacker can use two different addresses to borrow from himself at different interest rates. Proof of Concept AS the papr interest rates and the papr trading price are in a constant feedback loop. Interest rates are programmatically updated on chain as a...

Early user can break the minting of LP Tokens

Lines of code Vulnerability details Impact The attack vector is the same as TOB-YEARN-003, where users may not receive liquidity tokens in exchange for their baseTokenAmount and fractionalTokenAmount deposited if the total baseTokenAmount has been manipulated through a large “donation”. In the...

Priority queue min accounting breaks when nodes are split in two

Lines of code Vulnerability details The README states If two users place bids at the same price but with different quantities, the queue will pull from the bid with a higher quantity first, but the data-structure used for implementing this logic, is not used properly and essentially has its data...

Any user which holds Raes tokens can infinitely freeze NFT in OptimisticListingSeaport

Lines of code Vulnerability details Description OptimisticListingSeaport exposes propose method to create new proposal, and rejectProposal to remove a listing in proposal stage. In propose, proposer commits a certain amount of collateral: // Sets collateral amount to pending balances for withdraw...

User can send a proposal and instantly take back their collateral, keeping the proposal active without risking any Raes amount.

Lines of code Vulnerability details Description In OptimisticListingSeaport.sol, users call propose to set a new proposal. The pendingBalance is updated immediately for the calling proposer: // Sets collateral amount to pending balances for withdrawal pendingBalancesvaultproposedListing.proposer ...

Rounding down leads to breakage of the xy curve calculation

Lines of code Vulnerability details Impact When needing to calculate the inputAmount required to receive a certain amount of fractional tokens called outputAmount, we are deriving from the xy = k curve used on the Uniswap V2 protocol. Proof of Concept Some maths: The so-called curve equation is: ...

PRICES CAN BE MANIPULATED WHEN LIQUIDITY IS VERY LOW

Lines of code Vulnerability details Impact Base and fractional token prices in the pool can be manipulated and set to values severely deviating from the originally intended price ratio right after the pool has been created. At this point, liquidity in the pool is deemed zero or exceptionally thin...

Users could receive 0 LPTokens when calling add

Lines of code Vulnerability details Impact The addQuote function in Pair.sol calculates the amount of LPTokens received for the amount of baseTokens and fractionalTokens sent. If LPToken's supply 0 then the min amount of baseTokenShare and fractionaTokenShare is used. When the add function is use...

MISSING HANDLE FOR DIRECT SEND OF TOKEN

Lines of code Vulnerability details Impact The current implementation of the protocol does not handle situations when tokens are sent directly to the pair contract. Tokens directly send to the contract can affect the calculation of baseTokenReserves which affect buyQuoute and sellQuoute. Below is...

[M-0] Unhandled return values of transfer

Lines of code Vulnerability details c4udit Report Issues found M-0 Unhandled return values of transfer Impact Some implementations of transfer could return ‘false’ on failure instead of reverting. Findings: src\Pair.sol::85 = transferFrommsg.sender, addressthis, fractionalTokenAmount;...

sellQuote might lead to unexpected reverts when returning zero

Lines of code Vulnerability details Impact the implementation of sellQuote follows the logic of getAmountOut from Uniswap V2 Library. However it doesn't add +1 as the original implementation, this could make the function return zero and lead to reverts. Proof of Concept Tools Used Manual review...

Protocol's fractional token assumes that each NFT in a collection has the same value

Lines of code Vulnerability details Impact User can cheat the system by wrapping getting fractional tokens a low value NFT and unwrapping a high value NFT selling the same fractional tokens. Pair creator might lose out. Proof of Concept Pair.wrap takes in an array of tokenIds and an array of...

When user of GroupBuy is a contract, refunds will be permanently frozen.

Lines of code Vulnerability details Description claim function is used in GroupBuy to mint Raes proportional to user's contribution to the purchased NFT. withdrawBalance is used to get back funds which are not part of the contribution. They both contain an unsafe call with ETH. For example:...

GroupBuy does not properly refund users

Lines of code Vulnerability details Impact On a successful purchase, users can call claim on the GroupBuy contract to mint and refund. The refunded amount is userContributions - summinReservePricesqty - pendingBalances. In case of the actual purchase price minReservePrices, the difference is not...

rejectProposal/rejectActive/cancel did not update pendingBalances

Lines of code Vulnerability details Impact In the OptimisticListingSeaport contract, pendingBalances represents the number of Rae tokens sent to the contract by the user when creating the proposal, which can be withdrawn in the withdrawCollateral function. function withdrawCollateraladdress vault...

GroupBuys that are completely filled still don't raise stated target amount

Lines of code Vulnerability details Description createPool in GroupBuy.sol creates a new contribution pool around an NFT. It specifies a target initialPrice as minimum amount of ETH the NFT will cost, and totalSupply which is the number of Raes to be minted on purchase success. minBidPrices is...

contribute() locks too much ETH from the user

Lines of code Vulnerability details Impact In the contribute function of the GroupBuy contract, even if the filledQuantity is less than quantity, all the ETH provided by the user is locked in the contract, and the user can only call claim to get it back after purchasing NFT or Pool expires, which...

Attacker can delay proposal rejection

Lines of code Vulnerability details Impact In OptimisticListingSeaport.rejectProposal, it revert if proposedListing.collateral if proposedListing.collateral proposedListing.collateral -= amount; Proof of Concept 1. Attacker propose at 10000 collateral at a very low price 2. Bob try to reject it b...

Invalid tokens can be added to the pair

Lines of code Vulnerability details Impact merkleRoot is a bytes32 and it is compared to bytes230 which makes it possible for a non-zero merkleRoot to be set in the constructor and yet still all tokens will be declared as valid Proof of Concept Tools Used Manual Audit Recommended Mitigation Steps...

User didn't get an lpToken when trying to add liquidity to the pair with some baseTokenAmount

Lines of code Vulnerability details Impact User didn't get an lpToken when trying to add liquidity to the pair with some baseTokenAmount. The user lost their asset since they didn't get any lpToken Proof of Concept Inside Pair.sol contract, the add function exist for adding liquidity to the pair...