Optimism

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.

Since Optimism uses a fork of Geth, issues which are responsibly disclosed to upstream cannot be "replayed" against Optimism’s bug bounty program if the vulnerability has already been made public. If the vulnerability is disclosed to Optimism at the same time as upstream Geth, the vulnerability is eligible for the bug bounty program.

All smart contract bug reports must come with a PoC in order to be considered for a reward.

For KYC, OptimismPBC will request a W-9 if you reside in the US or a W-8 if you reside outside the US.

Critical vulnerabilities are further capped at 10% of economic damage, with the main consideration being the funds affected in addition to PR and brand considerations, at the discretion of the team. However, there is a minimum of USD 75 000 for Critical bug reports.

For testing any exploits involving cross-domain transactions, we recommend working with our dockerized services and modifying our integration tests

The following known issues are considered to be out of scope of this bug bounty program.

Known issues:

Blockchain / DLT:

When running in non-archive mode, op-geth has difficulty executing deep reorgs. We are working on a fix.

Smart Contracts:

• Proof of whale based attacks on Fault Proofs.
• There appears to be an obvious bug which would allow an attacker to withdraw a fake ERC20 token from L2 in exchange for a real ERC20 (such as WBTC) token on L1. There is no check in the L2StandardBridge, however the withdrawal is prevented from finalizing by a check in the L1StandardBridge. Naturally if you do find a way to circumvent our protections, then we would reward you.
• A bug in ResolvedDelegateProxy.sol which could result in a storage slot key collision overwriting the address of the implementation. This bug is dependent on the layout of the implementation contract, and Optimism is not affected.
• There is an edge case in which ETH deposited to the OptimismPortal by a contract can be irrecoverably stranded:
  • When a deposit transaction fails to execute, the sender’s account balance is still credited with the mint value. However, if the deposit’s L1 sender is a contract, the tx.origin on L2 will be aliased, and this aliased address will receive the minted on L2. In general the contract on L1 will not be able to recover these funds. We have documented this risk and encourage users to take advantage of our CrossDomainMessenger contracts which provide additional safety measures.
• Sending cross-chain messages with very large amounts of data, or very specific amounts of gas can open up griefing attacks causing the sender’s funds to be stuck and requiring an upgrade to release them.
• Deposit transactions can be griefed at a cost to the attacker, by filling up the MAX_RESOURCE_LIMIT. This issue is mitigated by PR 5064, which does not completely resolve the issue but does increase the cost of a sustained griefing attack. A more complete fix will require architectural changes.
• There are various ‘foot guns’ in the bridge which may arise from misconfiguration of a token. To minimize complexity our bridge design does not try to prevent all forms of developer and user error. Examples of such foot guns include:
  • Having both (or neither of) the local and remote tokens be OptimismMintable.
  • Tokens which dynamically alter the amount of a token held by an account, such as fee-on-transfer and rebasing tokens.

Payouts are handled by the Optimism team directly and are denominated in USD. All payouts are done in USDC.