Gro

Gro protocol is a stablecoin yield aggregator that tranches risk and yield. The first two products built on it are the PWRD stablecoin with deposit protection and yield, and Vault with leveraged stablecoin yields.

The protocol delivers DeFi yields by continuously optimising a range of market neutral yield strategies, including lending income, trading fees from Automated Market Makers, and protocol incentive farming. What makes it unique is the Gro Risk Balancer, a novel risk tranching module that distributes smart contract and stablecoin risk in a targeted way.

Initially the protocol has two risk- and yield-tranched products: the PWRD stablecoin and the Vault. All deposits are algorithmically and non-custodially allocated to a set of strategies. Depositors into the Vault receive a higher proportion of system yields but also take on extra smart contract and stable coin risk. Inversely, the PWRD stablecoin receives a smaller portion of the system yield but is protected against these risks.

For more information about Gro, please visit https://gro.xyz/.

This bug bounty program is focused on their smart contracts, and is focused on preventing the following impacts:

• Thefts and/or freezing of principal funds in protocol of any amount
• Thefts and/or freezing of unclaimed yield of any amount
• Temporary freezing of funds for X minutes/hours/days
• Smart contract fails to deliver promised returns
• Sets of protocol interactions which benefit the person making these interactions at the expense of other users invested in the protocol, or the protocol itself
• Protocol and/or oracle interactions which result in unfair allocation of gains to specific users

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.

While the protocol currently has a 0.5% withdrawal fee on PWRD, a bug bounty of up to USD 500 000 can be claimed if a loss of funds can be created when the withdrawal fee is set to 0.

Critical bug reports are capped at 10% of economic damage, primarily taking into consideration the funds at risk, but can also consider other factors such as branding and PR, all fully at the discretion of the team. However, there is a minimum reward of USD 50 000.

Payouts are handled by the Gro team directly and are denominated in USD. However, payouts are done in USDC.

For added reference, here are the external dependencies that interact with the Gro protocol:

DAI - https://etherscan.io/address/0x6B175474E89094C44Da98b954EedeAC495271d0F

USDC - https://etherscan.io/address/0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48

USDT - https://etherscan.io/address/0xdAC17F958D2ee523a2206206994597C13D831ec7

Curve3Pool - https://etherscan.io/address/0xbEbc44782C7dB0a1A60Cb6fe97d0b483032FF1C7

3Crv - https://etherscan.io/address/0x6c3F90f043a72FA612cbac8115EE7e52BDe6E490

For now, no GitHub repo is publicly available, and so a PoC is not required for any bug report. In the event of a PoC being required for final validation of a bug to clarify disagreements on a bug report’s validity, access will be provided.

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.

Smart Contracts

• Thefts and/or freezing of principal funds in protocol of any amount
• Thefts and/or freezing of unclaimed yield of any amount
• Temporary freezing of funds for any period
• Smart contract fails to deliver promised returns
• Sets of protocol interactions which benefit the person making these interactions at the expense of other users invested in the protocol, or the protocol itself
• Protocol and/or oracle interactions which result in unfair allocation of gains to specific users

We are especially interested in receiving and rewarding vulnerabilities of the following types:

Smart Contracts and Blockchain

• Re-entrancy
• Logic errors
  • including user authentication errors
• Solidity/EVM details not considered
  • including integer over-/under-flow
  • including rounding errors
  • including unhandled exceptions
• Trusting trust/dependency vulnerabilities
  • including composability vulnerabilities
• Oracle failure/manipulation
• Novel governance attacks
• Economic/financial attacks
  • including flash loan attacks
• Congestion and scalability
  • including running out of gas
  • including block stuffing
  • including susceptibility to frontrunning
• Consensus failures
• Cryptography problems
  • Signature malleability
  • Susceptibility to replay attacks
  • Weak randomness
  • Weak encryption
• Susceptibility to block timestamp manipulation
• Missing access controls / unprotected internal or debugging interfaces

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