Decentralized exchange, Uniswap, has delisted Tether Gold and stock tokens. The exchange cited regulatory concerns, which left people wondering about its “decentralized” property. Based on Ethereum, Uniswap is known to be one of the largest decentralized trading platforms. However, its “decentralized” status is now questioned by crypto users after it decided to delist certain tokens from the trading […]
De bitcoin (BTC) koers doet het nog altijd goed in een verder groen kleurende markt. Traders wachten al lang op de vorming van een bodem en een duurzaam herstel naar hogere
Het bericht Bitcoin (BTC) koers zet rally voort en nadert $35.000 – axie infinity (AXS) doet er nog een schep bovenop! verscheen eerst op Dutch Crypto Talk.
Self-employed individuals have multiple options to save for retirement and invest in a tax-efficient manner. One of those options, the Solo 401(k), can be particularly attractive to entrepreneurs running their own business, including those with both a 9-to-5 corporate employer and a “side-hustle” that earns them additional income. Q2 2021 hedge fund letters, conferences and […]
After garnering the approval of a supermajority in parliament, El Salvador enacted its Bitcoin Law, essentially becoming the world’s first country to adopt bitcoin as legal tender. The Bitcoin Law was passed just hours after President Nayib Bukele first revealed his intentions to introduce it. The brief time period between Bukele’s surprise announcement and the […]
Every now and then, a job post will trigger a cascade of rumors in the cryptoverse as observers want to know whether a tech giant like Apple or Facebook is preparing to adopt cryptocurrencies. This happened recently with Amazon, which published a new job listing that looks to hire a digital currency and blockchain product […]
A series of attacks compromised several Binance Smart Chain (BSC) projects in May. Following PancakeBunny, its three forks projects — AutoShark, Merlin Labs, and PancakeHunny — were also attacked using similar techniques. PancakeBunny suffered the most costly attack of the four, which saw nearly $45M in total damages. In this article, Dr. Chiachih Wu, Head of the Amber Group Blockchain Security Team, elaborates on the details behind the attacks on the three copycats. Copycats AutoShark was attacked five days after PancakeBunny, followed by Merlin Labs and PancakeHunny, respectively. The following is an analysis of the problems and possible attack techniques for these three forked projects. In the SharkMinter.mintFor() function, the amount of rewarding SHARK tokens to be minted (i.e., mintShark) is derived from sharkBNBAmount computed by tokenToSharkBNB() in line 1494. However, tokenToSharkBNB() references the current balance of flip, which makes it a vulnerable point. One could assume that the amount of tokens received in line 1492 is equal to the amount of the flip balance. Still, a bad actor could manipulate the flip balance simply by sending in some flip tokens right before the getReward() call and indirectly breaking the logic of tokenToSharkBNB(). In the underlying implementation of tokenToSharkBNB() , there’s another attack surface. As shown in the above code snippet, _flipToSharkBNBFlip() removes liquidity from ApeSwap (line 1243) or PantherSwap (line 1262) and converts the LP tokens into SHARK+WBNB. Later on, the generateFlipToken() is invoked to convert SHARK+WBNB into SHARK-BNB LP tokens. Inside generateFlipToken() , the current SHARK and WBNB balances of SharkMinter (amountADesired, amountBDesired) are used to generated LP tokens and the amount of LP tokens are returned to mintFor() as sharkBNBAmount. Based on that, the bad actor could transfer SHARK+WBNB into SharkMinter to manipulate the amount of SHARK tokens to be minted as well. The loophole in PancakeHunny is identical to that found in AutoShark, in that the bad actor can manipulate HUNNY reward minting with HUNNY and WBNB tokens. Compared to AutoShark and PancakeHunny, Merlin Labs’ _getReward() has a more obvious vulnerability. The code snippet above shows that the performanceFee could be manipulated by the balance of CAKE, which indirectly affects the MERL rewards minting. However, the nonContract modifier gets rid of flash loans. Even without an exploit contract, the bad actor could still profit through multiple calls. Reproducing AutoShark Attack To reproduce the AutoShark hack, we need to first get some SHARK-BNB-LP tokens from PantherSwap. Specifically, we swap 0.5 WBNB into SHARK (line 58) and transfer the rest WBNB with those SHARK tokens into PantherSwap for minting SHARK-BNB-LP tokens (line 64). Later on, we deposit those LP tokens into AutoShark’s StrategyCompoundFLIP contract (line 69) to qualify for rewards. Note that we purposely only deposit half of the LP tokens in line 69. The second step is to make getReward() go into the SharkMinter contract. In the above code snippet, we know that the reward can be retrieved by the earned() function (line 1658). Besides, 30% of the reward (i.e., performanceFee) should be greater than 1,000 (i.e., DUST) to trigger the SharkMinter.mintFor() in line 1668. Therefore, in our exploit code, we transfer some LP tokens to the StrategyCompoundFLIP contract in line 76 to bypass the performanceFee > DUST check and trigger the mintFor() call. Since we need a lot of WBNB+SHARK to manipulate SharkMinter, we leverage PantherSwap’s 100k WBNB via a flash-swap call in line 81. In the flash-swap callback, pancakeCall(), we exchange half of the WBNB into SHARK and send the SHARK with the remaining 50,000 WBNB to the SharkMinter contract to manipulate the reward minting. The next step is to trigger getReward() when the SharkMinter receives the WBNB+SHARK tokens to mint a large amount of SHARK to the caller. The last step is to convert SHARK to WBNB, pay the flash loan, and walk away with the remaining WBNB tokens. In our experiment, the bad actor starts with 1 WBNB. With the help of flash loans, he profits from more than 1,000 WBNB being returned in one transaction. Reproducing PancakeHunny Attack The theory behind the PancakeHunny attack is similar to the AutoShark attack. In brief, we need to send a lot of HUNNY+WBNB to HunnyMinter before triggering getReward(). However, the HUNNY token contract has a protection mechanism called antiWhale to prevent large amount transfers. Therefore, flash loans do not work here. To bypass antiWhale, we create multiple child contracts and initiate multiple CakeFlipVault.deposit() calls via said contracts. In the above exploit code snippet, the LP tokens gathered in line 116 are divided into 10 parts and transferred to 10 Lib contracts in line 122 followed by Lib.prepare() calls for each of them. Inside Lib.prepare(), we approve() the CakeFlipVault to spend the LP tokens and invoke CakeFlipVault.deposit() to enable the later getReward() calls for minting rewarding HUNNY tokens. After preparing 10 Lib contracts, the main contract iterates each of them to: 1) swap WBNB to the maximum allowable amount of HUNNY; 2) transfer WBNB+HUNNY to HunnyMinter; 3) trigger getReward() via lib.trigger(); and 4) swap HUNNY back to WBNB. In the end, the bad actor with 10 WBNB earns around 200 WBNB from 10 runs of 10 Lib contracts operations. Reproducing Merlin Labs Attack As mentioned earlier, Merlin Labs has the noContract modifier to get rid of flash loan attacks. However, we could use a script to trigger the attack with multiple transactions initiated from an EOA (Externally Owned Account) address. The only difference is that someone may front-run the bad actor’s transaction to steal the profits. Similar to the AutoShark attack, we need to prepare enough LINK and WBNB (line 23), use them to mint WBNB-LINK-LP tokens (line 34), and deposit LP tokens into VaultFlipCake contract (line 38). The remaining actions are: Swapping WBNB to CAKE (line 42). Manipulating MERL minting by sending CAKE to VaultFlipToCake contract (line 50). Triggering getReward() in line 55 (a large amount of MERL tokens are minted). Swapping MERL back to WBNB and repeating the above steps multiple times. As mentioned earlier, if someone front runs step 3 right after step 2, that person could remove a large amount of MERL. In our experiment, the bad actor starts with 10 WBNB and walks away with around 165 WBNB by repeating the four steps 10 times. About Amber Group Amber Group is a leading global crypto finance service provider operating around the world and around the clock with a presence in Hong Kong, Taipei, Seoul, and Vancouver. Founded in 2017, Amber Group services over 500 institutional clients and has cumulatively traded over $500 billion across 100+ electronic exchanges, with over $1.5 billion in assets under management. In 2021, Amber Group raised $100 million in Series B funding and became the latest FinTech unicorn valued at over $1 billion. For more information, please visit www.ambergroup.io.
A series of attacks compromised several Binance Smart Chain (BSC) projects in May. Following PancakeBunny, its three forks projects — AutoShark, Merlin Labs, and PancakeHunny — were also attacked using similar techniques. PancakeBunny suffered the most costly attack of the four, which saw nearly $45M in total damages. In this article, Dr. Chiachih Wu, Head […]
According to the announcement from IOHK, “Project Alonzon testnet” has moved from Blue to White and is making it possible for Cardano to launch smart contracts. IOHK is the development team of the Cardano blockchain. The team made the announcement recently, revealing that the testnet is successful. Related Reading | Anthony Di Lorio To Leave Cryptocurrency Space For Philanthropic Initiatives In their announcement, the development team shared the success of the “#Alonzon testnet” fork to a new version, “#AlonzonWhitenode.” The announcement also disclosed that the latest version has commenced making blocks immediately. HARD FORK SUCCESSFUL: Delighted to report around 19.44 UTC today we successfully forked the #Alonzo testnet to the new #AlonzoWhite node. The new network is happily making blocks already. 1/5 — Input Output (@InputOutputHK) July 14, 2021 This new fork is taking the network a step further to launching smart contracts, which will be beneficial for its users. Cardano Testnet Had Limitations The first Cardano testnet may have offered smart contracts, but there were some limitations. The smart contract features it had were only for some people who are core insiders of the blockchain. Related Reading | Ether EFT Gets Approval From Brazilian Securities Regulator Given the upgrade that the team has announced, the network can now accommodate up to 500 validators, developers, and stake pool operators who will test the features. According to the announcement, the new Fork “Alonzon white” will run for 2 to 4 weeks. Then, it will upgrade to the Alonzo Purple, which is the final testnet for this current phase of its development. Before now, there has been some backlash against the network from the community. However, even with all those issues, the Cardano blockchain founder Charles Hoskinson assured the community that the project is moving as they planned it. He made this statement on Youtube, saying that the team is following the roadmap they set earlier for the project. Hoskinson also noted that Cardano had facilitated the sale of over $10 million worth of NFTs on its network. Also, apart from the NFTs, the founder mentioned that the network had facilitated assets sales worth tens of thousands. The ADA market is flourishing after a hectic week of trading in the red zone | Source: ADAUSD on TradingView.com He continued to assure the community that the release of Alonzo White to the Cardano mainnet will enable developers to launch NFTs, dApps, and other projects. More Developments in DeFi After the announcement of the Alonzo white fork, a DeFi and NFT marketplace, Spores Network disclosed that it had raised a whopping $2.3 million through its fundraising event yesterday, July 16, 2021. According to the company, it plans to utilize the best features of Cardano, such as low transaction costs, higher transaction throughput, and low carbon footprint, to make NFTs available for mainstream users. Related Reading | Nifty’s Inc. Partners With Warner Bros To Roll Out A Social NFT Platform In recent times, more and more artists and companies are joining the NFT market. Some notable ones include Dolce & Cabbana plus Sorare, a “fantasy soccer NFT platform.” In addition, Sorare recently closed a $532M in a funding round. All these interests and collaboration mean more gains to the Cardano network and the people who use it. Featured image from Pexels, chart from TradingView.com