Optimism
Optimism is a project dedicated to scaling Ethereum's technology and expanding its ability to coordinate people from across the world to build effective decentralized economies and governance systems.
ETH
Optimism
Defi
NFT
L1
L2
C/C++
Go
Solidity
Maximum Bounty
$2,000,042Live Since
14 January 2022Last Updated
07 October 2025Triaged by Immunefi
PoC Required
KYC required
Select the category you'd like to explore
Assets in Scope
Impacts in Scope
Severity
Critical
Title
Permanent freezing of funds
Severity
Critical
Title
Protocol insolvency
Severity
Critical
Title
Direct loss of funds
Severity
Critical
Title
Execute arbitrary system commands
Severity
Critical
Title
Retrieve sensitive data/files from a running server, such as:
- /etc/shadow
- database passwords
- blockchain keys (this does not include non-sensitive environment variables, open source code, or usernames)
Severity
Critical
Title
Taking and/modifying authenticated actions (with or without blockchain state interaction) on behalf of other users without any interaction by that user, such as:
- Changing registration information
- Commenting
- Voting
- Making trades
- Withdrawals, etc.
Severity
Critical
Title
Subdomain takeover with already-connected wallet interaction
Severity
Critical
Title
Direct theft of user funds
Severity
Critical
Title
Malicious interactions with an already-connected wallet, such as:
- Modifying transaction arguments or parameters
- Substituting contract addresses
- Submitting malicious transactions
Severity
Critical
Title
Injection of malicious HTML or XSS through metadata
Severity
Critical
Title
Loss of user funds by direct theft, other than unclaimed yield
Severity
High
Title
Network not being able to confirm new transactions (Total network shutdown)
Out of scope
Program's Out of Scope information
- explorer.optimism.io
- testnet-explorer.optimism.io
- vote.optimism.io
- retrofunding.optimism.io
- atlas.optimism.io
- public-grafana.optimism.io
- discord.optimism.io
- kyc.optimism.io
- kyb.optimism.io
- raas.optimism.io
- contribute.optimism.io
- superfest.optimism.io
- welovetheart.optimism.io
- Additionally, any other asset belonging to Optimism but not under Optimism’s control will also be out of scope.
Program’s custom out-of-scope information:
- Vulnerabilities in the implementation of ‘custom token bridges’ which are written by third parties for bridging tokens to their network
- Vulnerabilities requiring the user to have publicly exposed an API, such as JSON-RPC or the Beacon API, are out of scope of the bug bounty program.
- 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.
The following known issues are considered to be out of scope of this bug bounty program:
- All currently known issues with devp2p here: https://github.com/ethereum/devp2p/blob/master/rlpx.md#known-issues-in-the-current-version
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.
Default Out of Scope and rules
Blockchain/DLT specific
- Incorrect data supplied by third party oracles
- Not to exclude oracle manipulation/flash loan attacks
- Impacts requiring basic economic and governance attacks (e.g. 51% attack)
- Lack of liquidity impacts
- Impacts from Sybil attacks
- Impacts involving centralization risks
All categories
- Impacts requiring attacks that the reporter has already exploited themselves, leading to damage
- Impacts caused by attacks requiring access to leaked keys/credentials
- Impacts caused by attacks requiring access to privileged addresses (including, but not limited to: governance and strategist contracts) without additional modifications to the privileges attributed
- Impacts relying on attacks involving the depegging of an external stablecoin where the attacker does not directly cause the depegging due to a bug in code
- Mentions of secrets, access tokens, API keys, private keys, etc. in Github will be considered out of scope without proof that they are in-use in production
- Best practice recommendations
- Feature requests
- Impacts on test files and configuration files unless stated otherwise in the bug bounty program
- Impacts requiring phishing or other social engineering attacks against project's employees and/or customers