The profileId is incremented using ++_profileCounter inside the createProfile function without any overflow checks in createProfile function

Lines of code Vulnerability details Impact If this issue exists, profileCounter reaches the maximum value, it will wrap around and reset to its minimum value, which is 0 for unsigned integers in Solidity. This unintended behavior can have several negative impacts on the functioning of the contrac...

FollowNFT storage collision

Lines of code Vulnerability details Impact The lastFollowTokenId of FollowNFT contract has a storage collision. V2.0 storage layout: | lastFollowTokenId | uint128 | 17 | 0 | 16 | contracts/FollowNFT.sol:FollowNFT | | followerCount | uint128 | 17 | 16 | 16 | contracts/FollowNFT.sol:FollowNFT |...

processBlock() function forcibly wrapping a follow NFT could lock it without the owner's consent

Lines of code Vulnerability details Impact It locks the NFT against the owner's wishes. Proof of Concept processBlock is called by the LensHub when a profile is blocked It first checks if the follow NFT is wrapped using isFollowTokenWrapped If not wrapped, it forces wrapping by minting to the own...

The FollowNFT.initialize() function will never be executed

Lines of code Vulnerability details Impact This function Initializes the follow NFT. To check if a function has already been initialized use: if initialized revert Errors.Initialized; This condition will always end with revert Errors.Initialized, because in the constructor, when expanding the...

The onlyProfileOwnerOrDelegatedExecutor and whenNotPaused checks can be bypassed

Lines of code Vulnerability details Impact The LensHub.sol functions setProfileMetadataURI, setProfileMetadataURIWithSig, setFollowModule, setFollowModuleWithSig, collect, collectWithSig, act, actWithSig, setProfileImageURI, setProfileImageURIWithSig and others use...

Race condition in approve function can lead to more funds than intended being transferred

Lines of code Vulnerability details Impact The approve function from MToken.sol contains a front-running vulnerability that allows a user to spend more tokens than he should. Proof of Concept Lets take the following scenario: 1. Alice calls approveEve, 10. This permits Eve to spend 10 tokens from...

Possible integer underflow

Lines of code Vulnerability details Impact The previous FollowNFT implementation is different between v1.3 and v2.0. The followerCount is 0 for existing FollowNFTeven if lastFollowTokenId is not 0 after upgrade. // Old uint256 lastFollowTokenId slot splitted into two uint128s to include...

In LensBaseERC721.sol#_transfer() Lack of check from==to

Lines of code Vulnerability details Impact In LensBaseERC721.soltransfer balances of from and to are stored in temporary variables and after the subtration, addition operation the results are written to storage. In the second operation since the original balance is used in the addition operation,...

Current setUnderlyingPrice and setDirectPrice open to incorrect liquidation of users' positions and result in financial losses for users

Lines of code Vulnerability details Impact Price feeds can be affected by network congestion, causing transactions with outdated prices to be treated as current prices. As price feeds are crucial to the protocol's functioning, this situation can lead to incorrect liquidation of users' positions a...

Any user can claim rewards infinitely from the market without respecting the accrued rewards time

Lines of code Vulnerability details Impact calculateSupplyRewardsForUser updates the user accrued rewards based on the user balance of mTokens & on global and user indicies difference which is the time difference between the last reard claim and the current time . Comptroller contract: one of the...

Users cannot unfollow if they do not own the FollowNFT of the followTokenId used for their profile

Lines of code Vulnerability details Bug Description If the followTokenId of a profile is wrapped, users will only be able to unfollow if they are either: 1. The owner of the follow NFT. 2. An approved operator of the follow NFT's owner. This can be seen in the unfollow function of FollowNFT.sol:...

More collateral is seized than approved

Lines of code Vulnerability details Impact More collateral is seized outside of the comptroller's approved liquidation amount which means excess seizeTokens are transferred from the borrower to the liquidator leading to loss of funds Proof of Concept liquidateBorrowFresh first checks the allowanc...

liquidateBorrow() mTokens that do not enter the market can still be liquidated as collateral

Lines of code Vulnerability details Impact borrower's mTokens that do not join the market, but it still be Liquidation as collateral Proof of Concept If user wants to use mToken as collateral, the user needs to enter market with enterMarket function. / @notice Add assets to be included in account...

Users repay more than the approved amount.

Lines of code Vulnerability details Impact More tokens can be repaid than were approved leading to loss of funds Proof of Concept The repayBorrowFresh function does the following: 1. Checks if repay is allowed by calling comptroller.repayBorrowAllowed with the input repayAmount. 2. Fetches the...

approve() can be front-run

Lines of code Vulnerability details Impact In MToken.sol we have approve function: function approveaddress spender, uint256 amount override external returns bool address src = msg.sender; transferAllowancessrcspender = amount; emit Approvalsrc, spender, amount; ...

## [M-07] ERC20 return values not checked

Lines of code Vulnerability details Impact Tokens that don’t actually perform the transfer and return false are still counted as a correct transfer and the tokens remain in the SingleNativeTokenExitV2 contract and could potentially be stolen by someone else. Proof of Concept The ERC20.transfer an...

missing check for the max/min price in the chainlinkOracle.sol contract

Lines of code Vulnerability details Impact the chainlinkOracle.sol contract specially the getChainlinkPrice function using the aggregator v2 and v3 to get/call the latestRoundData. the function should check for the min and max amount return to prevent some case happen, something like this: if cas...

No Receive functiion in TemporalGovernor contract

Lines of code Vulnerability details Impact The function executeProposal in TemporalGovernor contract will fail, if there is a value to send with the call to the targets executeProposal function could send native token out along with a call to the targets encoded in vm.payload, but the current...

Unauthorized Admin Transfer Vulnerability

Lines of code Vulnerability details Description The bug in this contract is that it doesn't handle the case when the pendingAdmin is set to the zero address address0. As per the condition msg.sender == address0, the if statement can be bypassed if an attacker sets pendingAdmin to the zero address...

Anyone can permanently disable the token guardian for their wallet by calling this one DANGER__disableTokenGuardian function

Lines of code Vulnerability details Impact A hacker could call DANGERdisableTokenGuardian, instantly disable the guardian and steal tokens or make malicious approvals Proof of Concept The DANGERdisableTokenGuardian function is risky and should be reconsidered. The main issue is that it allows...

function _queueProposal not checking if the required time is passed to allow proposal to set to the queue list

Lines of code Vulnerability details Impact in the queueProposal function there is no check for if the requested time is passed to allow queue the proposal. in this case any proposal after creating can be added to the queue list. Proof of Concept the TemporalGovernor.sol contract have a variable...

[ H ] Infinite loop in calculateNewIndex prevents tokens from being minted and rewards from being distributed

Lines of code Vulnerability details Impact Recursive calls from calculateNewIndex in MultiRewardDistributor will result in an infinite loop and out of gas errors, preventing tokens from being minted and rewards being sent to some users as disburseSupplierRewardsInternal will not be called. Proof ...

the unbounded approve function allows a front-running vulnerability due to setting unlimited allowance.

Lines of code Vulnerability details Impact if approve is called with a very high allowance, the spender can drain the owner's entire balance. Proof of Concept approve allows setting an allowance to any arbitrary uint256 value, including typeuint.max. This effectively gives unlimited approval to t...

Users can unfollow through FollowNFT contract when LensHub is paused by governance

Lines of code Vulnerability details Bug Description When the LensHub contract has been paused by governance state set to ProtocolState.Paused, users should not be able unfollow profiles. This can be inferred as the unfollow function has the whenNotPaused modifier: LensHub.solL368-L371 function...

exitMarket was missing reentrancy protection.

Lines of code Vulnerability details Impact exitMarket function in Comptroller.sol function was missing checks to prevent reentrancy exploitation. This allowed an attacker to call exitMarket multiple times before the newly borrowed amount was recorded. Since the borrowed amount was not actually...

Default Account fallback lack payable

Lines of code Vulnerability details Impact fallback lack payable,will lead to differences from the mainnet, and many existing protocols may not work Proof of Concept DefaultAccount Defined as follows: DefaultAccount The implementation of the default account abstraction. This is the code that is...

The owner can call _upgrade directly, skipping executeLensV2Upgrade.

Lines of code Vulnerability details Impact Loss of funds due to skipped checks before transfers Invalid system state due to assuming conditions not verified Hiding failed upgrade due to skipped revert/events Proof of Concept upgrade is missing an onlyOwner modifier By calling upgrade directly, th...

Potential Stale Data Due to Inadequate Round Validation

Lines of code Vulnerability details Impact Even tough the dev is checking if the data is stale or not some valid prices could still be considered as invalid because of this line: answeredInRound == roundId, sometimes the answeredInRound might be greater than roundId and would still be valid but i...

safe32 WILL RESTRICT THE DURATION OF MultiRewardDistributor._addEmissionConfig FUNCTION USABILITY

Lines of code Vulnerability details Impact The MultiRewardDistributor.addEmissionConfig function is used to add a new emission configuration for a specific market. The addEmissionConfig function constructs the MarketConfig configuration struct using the input parameters to the function. The...

First mint user can inflate share which can steal asset from other user

Lines of code Vulnerability details Impact A well know inflation attack/first deposit mint bug. The attacker can steal assets from other user's deposit mint. Proof of Concept The Moonwell project is a fork from the Compound Protocol. The MToken the MToken on Compound represents a yield-bearing...

Attacker can Steal all eths of WETHRouter.sol through redeem function

Lines of code Vulnerability details Impact An attacker can Steal eths through redeem function in WETHRouter.sol as you know the contract does the redeem process and redeem user mTokens to ETHs, and as you know we have the function of mint which is the opposite of this and users deposit ETH in ord...

Missing check of how recent the price is can lead to stale price being used in the protocol

Lines of code Vulnerability details Impact In the ChainlinkOracle.sol file, in the function getChainlinkPriceAggregatorV3Interface feed, there is the check requireupdatedAt != 0, "Round is in incompleted state";. However, there is no check to see that the price is recent and acceptable. If there ...

Using LensBaseERC721::_safeTransfer may lead to tokens being locked forever

Lines of code Vulnerability details Impact As we are all aware of, the OZ Address.sol function isContract can be bypassed because as the docs says: It is unsafe to assume that an address for which this function returns false is an externally-owned account EOA and not a contract. Among others,...

Migration of Profiles can fail due to existance of same handle

Lines of code Vulnerability details Impact Some profiles cannot be migrated to V2 if their handle tokenId has already been minted. Proof of Concept A handle can be minted in the LensHandles contract before a profile that would have the same handle is migrated from V1. When the profile attempts to...

Cannot unfollow a profile without having access to the Follow NFT

Lines of code Vulnerability details Impact In scenarios where a user fails to unfollow a profile before selling his follow NFT, he could forever be unable to unfollow the profile. Proof of Concept A user could sell his follow NFT without unfollowing a profile. If the new owner of the follow NFT...

Inability of Followers and Followees to Commenting

Lines of code Vulnerability details Impact The lack of functionality restricts interaction and engagement between the profile owner and their followers or the users they follow. This limitation diminishes the platform's value, as users who are interested in a post or have a genuine reason to...

Missing owner check on from when transferring tokens

Lines of code Vulnerability details Impact The LensBaseERC721.transferFrom/safeTransferFrom/burn they check approvals on msg.sender through isApprovedOrOwnermsg.sender, tokenId, it is never checked that the specified from parameter is actually the owner of the NFT. An attacker can decrease other...

Front-Running Vulnerability in LensHub.sol's commentWithSig and quoteWithSig Functions

Lines of code Vulnerability details Impact A vulnerability has been discovered in LensHub.sol's commentWithSig and quoteWithSig functions. This vulnerability potentially enables an attacker to disrupt users' actions by front-running transactions, resulting in undesirable modifications of comments...

Privacy Violation: Unauthorized Access to Blocking Status of Profiles

Lines of code Vulnerability details Impact The smart contract contains a critical privacy violation that allows unauthorized users to access the blocking status of profiles. The isBlocked function, which is intended to check if one profile is blocked by another, lacks proper access controls and...

wrap after unfollow is enabled

Lines of code Vulnerability details Impact wrap after unfollownft is enabled , cause many problems Proof of Concept by design, wrap after unfollowed is not allowed,but it seems that it's possible due to lack of limitation. poc below: add below script in FollowNFTTest.t.sol //forge test --match-te...

Unchecked Call Return Value of ERC20 Functions

Lines of code Vulnerability details Impact The return value of 'transfer' and 'transferFrom' should be verified since these two functions may only return false but not cause execution reverted once fail. If not properly handled, it might incur asset losses to users and the project party. Tools Us...

Unauthenticated Access of withdrawToTreasury Makes _distributeFees Not Work

Lines of code Vulnerability details Impact Since the function withdrawToTreasury lacks authority control, anyone can call withdrawToTreasury to transfer erc20 token or native coin held by the contract to the treasury. This will indirectly cause the transaction which calls function...

Lack of Preventing Multiple Follows to the Same Profile ID

Lines of code Vulnerability details Impact The absence of a check for multiple follows to the same profile ID poses a significant security and integrity risk for the smart contract. By exploiting this vulnerability, a malicious user could inflate the number of followers for a particular profile I...

Incorrect Signature Validation in LensHub Contract

Lines of code Vulnerability details Description The LensHub contract contains two functions, "setFollowModuleWithSig" and "setProfileImageURIWithSig," that allow users to set a follow module and profile image URI, respectively, for a profile using EIP712 signatures for verification. However, the...

Unauthorized Profile "Follow" Operation Bug

Lines of code Vulnerability details Description The contract's followWithSig function allows any user with a valid signature to execute "follow" operations on behalf of any profile without properly verifying the ownership of the profile or checking if the signer is an approved executor. This bug...

Function initialize Not Work

Lines of code Vulnerability details Impact As mentioned in the comment of the function initialize, "This is called right after deployment by the LensHub, so we can skip the onlyHub check". However, when the contract FollowNFT is deployed, the state variable initialized is set to true in the...

tryMigrate() has onlyHub modifier but it's called from LensV2Migration

Lines of code Vulnerability details Impact In FollowNFT.sol, tryMigrate function has onlyHub modifier as other functions that are supposed to be called by LensHub such as follow and unfollow. These functions are called via delegatecall and LensHub is preserved as msg.sender. The problem is that t...

Malicious actors could pass in huge arrays to disrupt service availability (DOS) in the updateVotingPower function

Lines of code Vulnerability details Impact The contract is stopped from being usable by legitimate users if the attacker repeatedly spammed large arrays Proof of Concept The updateVotingPower function currently only checks that the array is = 50: While 50 may be a reasonable limit for normal usag...

A malicious manager could revoke grants early and steal unvested tokens.

Lines of code Vulnerability details Impact A malicious manager can: Revoke a grant before its expiration. Take all tokens not yet vested/withdrawn based on the vesting schedule. Deprive the grant owner of tokens they should have later received if vesting continued. Proof of Concept A The...

ARCDVestingVault.sol::revokeGrant can revert for zero value transfers with weird ERC20 tokens.

Lines of code Vulnerability details Impact The call to revokeGrant by a Manager before the cliff time has been reached can cause the call to revert for some ERC20 tokens, this can stop the manager from revoking a grant from a given recipient. Proof of Concept The following scenario could occur,...