Xend Finance (XF) is a decentralized Credit Union protocol built to optimize, improve and add value to the core operations of credit unions globally. Xend Finance gives individuals, groups, cooperatives and credit unions in countries with unstable currencies access to a global trustless and stable-currency savings, lending, investing and borrowing network.
Xend Finance has also developed a Layer 2 DeFi infrastructure that automatically seeks out the best yields in DeFi by optimizing and automatically aggregating existing DeFi lending protocols. This infrastructure was designed to maintain high yield with influx of users and capital from traditional finance into decentralized finance as well as provide a better user experience for investors seeking the best yields in DeFi.
Centralized and Fiat savings platforms are always limited by fees and cross-border payment regulations that limit investing in other countries. With Xend Finance, anyone, whether individuals, cooperatives or credit unions, anywhere in the world can save, lend and invest in different DeFi protocols and start earning interests instantly.
For more information about Xend Finance, please visit https://xend.finance.
This bug bounty program is focused on their smart contracts and is focused on preventing:
- Loss of user funds staked by freezing or theft
- Theft of unclaimed yield
- Unable to call smart contract
- Smart contract fails to deliver promised returns
- Temporary freezing of funds
- Loss of governance funds
- Loss of treasury funds
Rewards by Threat Level
Rewards are distributed according to the impact of the vulnerability based on the Immunefi Vulnerability Severity Classification System. This is a simplified 5-level scale, with separate scales for websites/apps and smart contracts/blockchains, encompassing everything from consequence of exploitation to privilege required to likelihood of a successful exploit.
No PoC is required for smart contract bug reports.
Known issues from their previous audits are considered out-of-scope:
Payouts are handled by the Xend Finance team directly and are denominated in USD. Payouts are done in USDT.
- USD $50,000
- USD $20,000
Assets in scope
- Smart Contract - xvUSDTType
- Smart Contract - xvUSDCType
- Smart Contract - xvBUSDType
- Smart Contract - StrategyUgoHawkVenusUSDTFarmType
- Smart Contract - StrategyUgoHawkVenusUSDCFarmType
- Smart Contract - StrategyUgoHawkVenusBUSDFarmType
- Smart Contract - xUSDTType
- Smart Contract - xUSDCType
- Smart Contract - xAAVEType
- Smart Contract - xWBTCType
- Smart Contract - EarnAPRWithPoolType
- Smart Contract - APRWithPoolOracleType
Impacts in scope
Only the following impacts are accepted within this bug bounty program. All other impacts are not considered as in-scope, even if they affect something in the assets in scope table.
- Loss of user funds staked (principal) by freezing or theftCriticalImpact
- Loss of governance fundsCriticalImpact
- Loss of treasury fundsCriticalImpact
- Theft of unclaimed yieldHighImpact
- Temporary freezing of funds for any amount of timeHighImpact
- Unable to call smart contractMediumImpact
- Smart contract fails to deliver promised returnsLowImpact
Out of Scope & Rules
The following vulnerabilities are excluded from the rewards for this bug bounty program:
- Attacks that the reporter has already exploited themselves, leading to damage
- Attacks requiring access to leaked keys/credentials
- Attacks requiring access to privileged addresses (governance, strategist)
Smart Contracts and Blockchain
- Incorrect data supplied by third party oracles
- Not to exclude oracle manipulation/flash loan attacks
- Basic economic governance attacks (e.g. 51% attack)
- Lack of liquidity
- Best practice critiques
- Sybil attacks
The following activities are prohibited by this bug bounty program:
- Any testing with mainnet or public testnet contracts; all testing should be done on private testnets
- Any testing with pricing oracles or third party smart contracts
- Attempting phishing or other social engineering attacks against our employees and/or customers
- Any testing with third party systems and applications (e.g. browser extensions) as well as websites (e.g. SSO providers, advertising networks)
- Any denial of service attacks
- Automated testing of services that generates significant amounts of traffic
- Public disclosure of an unpatched vulnerability in an embargoed bounty