We Need Smarter Smart Contracts To Prevent DeFi Hacks

By Waqas The smart contracts that govern DeFi are littered with exploitable code, and hackers understand that since hundreds of millions of crypto funds have been siphoned off due to this very issue. This is a post from HackRead.com Read the original post: We Need Smarter Smart Contracts To Preve...

#bulkExecute() can reenter to steal funds

Lines of code Vulnerability details Impact ExchangebulkExecute can reenter, and internal execution of delegatecall is allowed to fail, not revert, malicious users can reenter to steal funds Proof of Concept Assumptions: There is a malicious user alice,with NFT for sale, paid through eth If user b...

On _returnDust, call opcode's return value not checked

Lines of code Vulnerability details Impact The call opcode's return value not checked, which could leads to the originator lose funds. Proof of Concept The caller of Exchange.sol::execute or Exchange.sol::bulkExecute could be a contract who may not implement the fallback or receive function, when...

Exchange refund operation will return all ETH stored in the contract instead of the remaining amount from the exchange operation

Lines of code Vulnerability details Exchange refund operation will return all ETH stored in the contract instead of the remaining amount from the exchange operation The function that refunds remaining ETH in the Exchange contract will send back all the balance present in the contract instead of...

calling execute() may lead to stealing funds if some ETH is stuck on the contract

Lines of code Vulnerability details Impact if some Ether is sent erroneously or not to the contract, anyone that calls correctly LooksRareAggregator.execute will be able to steal those coins. to execute the function using ethers as payment, these conditions must be true: there is at least a trade...

Public to all funds escape

Lines of code Vulnerability details Description The LooksRareAggregator smart contract implements a bunch of functions to escape funds by the contract owner see rescueETH, rescueERC20, rescueERC721, and rescueERC1155. In this way, any funds that were accidentally sent to the contract or were lock...

Mssing Crucial Checks When Unlocking funds for Withdraw Requests from L2

Lines of code Vulnerability details Impact Atomicity literally does not exist when users from L2 initiate a withdrawal by burning funds on the contract and sending the message to L1. This is giving malicious attackers plenty of time to stealthily launch a series of small and yet sizable forgery o...

Providing the same address for the "base" and the "quote" tokens creates a risk of fund loss for the seller.

Lines of code Vulnerability details Impact The "createAuction" function requires the seller to input the address of a base and a quote token. However, there is no statement that checks whether or not these two provided addresses are the same. As a result, the seller could accidentally fill in an...

Contracts will not working correctly after February 2106. Vesting will be locked forever if withdrawn after February 2106.

Lines of code Vulnerability details Impact Contracts will not working correctly after February 2106. Migration takes costs and is risky. You shouldn't pass on this work to future programmers. You should fix it in the first place. In case anything went wrong during migration, a big fund loss will...

Rebasing tokens as Base tokens for the auction could be stuck in the contract or mean loss of funds for the las person to withdraw

Lines of code Vulnerability details Impact Use of rebasing tokens is not checked and could result it stuck funds, inability to cancel an Auction or withdraw due amounts of base token for the last one to call withdraw Proof of Concept If a rebasing token is used for the base token the balance held...

Seller can game the bidIndices[] in finalize()

Lines of code Vulnerability details Impact High bidders will be taken advantage of by malicious seller. It is likely that the high bidders will place bids above the market price, then the seller can effectively steal the price difference from them. And the other bidders are grieved, wasting time...

Bidder can abuse the bidIndices[] in finalize()

Lines of code Vulnerability details Impact finalize could be called by anyone, and the input array bidIndices is not sanity checked. Some malicious bidder can trick the bidIndices to always get the reserveQuotePerBase price. The seller would incur some loss. The other bidders are grieved, wasting...

Solmate safetransfer and safetransferfrom doesnot check the codesize of the token address, which may lead to fund loss

Lines of code Vulnerability details Impact In bid function, the safetransferfrom function doesn't check the existence of code at the token address. This is a known issue while using solmate's libraries. Hence this may lead to miscalculation of funds and may lead to loss of funds , because if...

[PNM-001] finalize with malicious input may allow multiple calls leading to fund draining

Lines of code Vulnerability details Description The finalize function of the contract SizeSealed is used to finalize an auction, allowing the auctioner or seller to be paid quote tokens and also eventually allowing successful bidders to withdraw base tokens. Once the finalize function is called,...

VARIABLE BALANCE TOKEN ASSOCIATED WITH LOSS AND LOCKING OF FUNDS

Lines of code Vulnerability details Impact ERC20 tokens that are either deflationary or re-basing down could have their respective balance change. The balance could become insufficient at the time of withdraw, refund or cancel to the bidders whose funds will be locked due to DOS. The way to take...

Attacker can steal any funds in the contract by state confusion (no preconditions)

Lines of code Vulnerability details HIGH: Attacker can steal any funds in the contract by state confusion no preconditions LOC: Description Auctions in SIZE can be in one of several states, as checked in the atState modifier: modifier atStateAuction storage a, States state if block.timestamp...

The door is open for anyone to become a cyber defender

Throughout Cybersecurity Awareness Month, Microsoft has highlighted the importance of cybersecurity and provided resources to help people and organizations stay safe. It’s great to have this month as a reminder, and even better if that awareness becomes a year-round endeavor. Education is really...

The door is open for anyone to become a cyber defender

Throughout Cybersecurity Awareness Month, Microsoft has highlighted the importance of cybersecurity and provided resources to help people and organizations stay safe. It’s great to have this month as a reminder, and even better if that awareness becomes a year-round endeavor. Education is really...

Reentrancy can increase allowance can be used to take more funds than expected

Lines of code Vulnerability details Reentrancy can increase allowance can be used to take more funds than expected In the same way as the typical front run of ERC20 approve/transferFrom, you would be able to take money when calling maliciousERC20.beforeApprove hook, this would realize a...

Users could accidentally burn() and lose fund

Lines of code Vulnerability details Impact If users accidentally burn the token, the fund will be lost. There does not seem any reason for the users to call the public burn function, only by mistake calling the method to lose self fund. Proof of Concept // contracts/enforcer/HolographERC721.sol...