SCHNOODLE

DESCRIPTION OF EVENTS

"PEER-TO-PEER, BLOCKCHAIN AUTOMATED REWARD KICKBACKS (BARK!) Schnoodle is a progressive DeFi peer-to-peer cryptocurrency with built-in Blockchain Automated Reward Kickbacks (BARK!) technology. Watch your balance grow automatically simply by holding SNOOD!"

"Designed and expertly coded from the ground up, Schnoodle is a first class DeFi cryptocurrency that you can truly trust. Schnoodle is an ERC-777 token that uses the latest technologies and practices to protect holders and ensure low gas fees. Key features: Upgradeability, oracle-based governance (DAO), multisig protection, eleemosynary fund, staking, farming, NFT rewards. Schnoodle really is man’s best friend!"

"Schnoodle is a fully decentralized, peer-to-peer cryptocurrency, owned entirely by its community (no team tokens). With oracle-based governance and multisig protection, Schnoodle will be the first of its kind to become a true DAO."

"All transfers incur a 1% eleemosynary donation, and a 4% fee that is proportionately distributed to all holders automatically as instant rewards. Sit back, relax, and watch your SNOOD balance grow on every transaction all day, every day."

"Schnoodle was incepted by our founder and CTO, Jason Payne, who decided to build Schnoodle because he was disillusioned with cryptocurrencies being released one after the other that had no real innovation, and were mostly copypasta smart contract clones of other tokens with a few tweaks. And those tweaks were typically convoluted layers of abstraction that usually benefited the dev team rather than the community."

"My ERC-777 smart contract (Schnoodle, symbol SNOOD) was attacked yesterday resulting in the entire liquidity in the UniswapV2Pair token being drained (104 ETH). The attack was by way of an attacker contract that performed a series of interactions with the liquidity token and my smart contract during its creation (txn here)."

"What I would like to know is, how did this attack take place, where is the vulnerability? And how do I protect against it? If this is an vulnerability in the SNOOD code, then how do I fix it? If it's a vulnerability in the UniswapV2Pair code related to ERC-777 tokens which is what SNOOD is, then I guess I would have to change my contract to ERC-20, or use UniswapV3Pair, or another DEX altogether."

"Seems to me that your error is here. Typically this kind of computation is done using fixed-point arithmetic or using a reflection * totalSupply / reflectedSupply calculation. In the case of transaction 0x9a6227ef97d7ce75732645bd604ef128bb5dfbc1bfbe0966ad1cd2870d45a20e , during the call to _spendAllowance, the _getStandardAmount call returns 0, even though the amount being transferred is significant. It's hard to tell what the intent of this code is, but the result is that the reflected amount isn't converted to a token amount, but is instead simply set to zero because _getReflectRate returns a large value. As a result, even though the UniswapV2 trading pair does not have an allowance set, the attacker is able to transferFrom the total balance of the pair to their attack contract. Subsequently, the attacker calls sync to force the pair to take up its new, vastly-decreased balance as the reserve. After that, it's a simple matter of swapping the stolen SNOOD tokens for the WETH left in the pair."

Schnoodle was a smart contract platform launched by Jason Payne, with nickname Neo, which allowed users to earn rewards simply by holding a SNOOD token. On June 18, 2022, Schnoodle lost $112K due to a hack which took advantage of an error in the reward calculation algorithm. The smart contract developer reached out on the Stack Exchange forums to get assistance in determine how their smart contract had been exploited. It is unclear if any compensation was provided to affected users.

BlockThreat - Week 25, 2022 - by Peter Kacherginsky (Mar 18)
solidity - Attack on ERC-777 smart contract and UniswapV2Pair resulting in 104 ETH liquidity drain - Ethereum Stack Exchange (Apr 4)
https://web.archive.org/web/20210514125449/http://schnoodle.finance/ (Apr 4)
Architecture | Schnoodle (Apr 4)
https://web.archive.org/web/20210804151546/https://schnoodle.finance/ (Apr 4)
https://web.archive.org/web/20231129092926/http://schnoodle.finance/ (Apr 4)
https://web.archive.org/web/20230922021254/http://schnoodle.finance/ (Apr 4)
SchnoodleV9 | Address 0xeac2a259f3ebb8fd1097aeccaa62e73b6e43d5bf | Etherscan  (Apr 4)
Ethereum Transaction Hash (Txhash) Details | Etherscan  (Apr 4)

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