Documentation and further resources can be found on [https://0x.org/docs/](https://0x.org/docs/)

For brevity regarding Smart Contract Assets

- the source tree on GitHub ([https://github.com/0xProject/0x-settler/tree/master/src](https://github.com/0xProject/0x-settler/tree/master/src)) 
- Deployer:
    - 0x00000000000004533Fe15556B1E086BB1A72cEae
    - any contract holding a "Deployer" ERC721 token (each a "Settler")
- AllowanceHolder:
    - 0x0000000000001fF3684f28c67538d4D072C22734
    - 0x0000000000005E88410CcDFaDe4a5EfaE4b49562
    - 0x000000000000175a8b9bC6d539B3708EEd92EA6c
- ERC2771 forwarding MultiCall
    - 0x00000000000000CF9E3c5A26621af382fA17f24f
- Cross-chain receiver factory
    - 0x00000000000000304861c3aDfb80dd5ebeC96325
- Pauser Safe module
    - 0x1CeC01DC0fFEE5eB5aF47DbEc1809F2A7c601C30
 

The scope is limited to these addresses, but *is not limited to any chain*. These contracts are deployed to many mainnet chains (the test-nets are not in scope). Presently the supported mainnet chains are: Ethereum mainnet, Ethereum Sepolia, Polygon, Base, Optimism, Arbitrum, Blast, Bnb, Mode, World Chain, Gnosis, Fantom Sonic, Ink, Monad testnet, Avalanche, Unichain, Berachain, Scroll, HyperEvm, Katana, Mantle, Taiko, and Linea. There will be many new chains added in the near future.

0x provides DEX aggregation services.  These services are made up of API, Web and mobile frontends, and smart contracts.  The primary services that are offered include: same chain token swaps, cross-chain swaps, gasless swaps, meta aggregation swaps.

Temporary freezing of funds

Injecting/modifying the static content on the target application without JavaScript (persistent), such as:  HTML injection without JavaScript, Replacing existing text with arbitrary text, Arbitrary file uploads, etc

Changing sensitive details of other users (including modifying browser local storage) without already-connected wallet interaction and with up to one click of user interaction, such as:  Email, Password of the victim etc.

Improperly disclosing confidential user information, such as:  Email address, Phone number, Physical address, etc.

Smart contract unable to operate due to lack of token funds

Block stuffing

Griefing (e.g. no profit motive for an attacker, but damage to the users or the protocol)

Theft of gas

Unbounded gas consumption

Changing non-sensitive details of other users (including modifying browser local storage) without already-connected wallet interaction and with up to one click of user interaction, such as:  Changing the name of user, Enabling/disabling notifications

Injecting/modifying the static content on the target application without JavaScript (reflected), such as:  Reflected HTML injection, Loading external site data

Redirecting users to malicious websites (open redirect)

Direct theft of any user funds, whether at-rest or in-motion

Permanent freezing of funds

Execute arbitrary system commands

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)

Taking down the application/website

Taking state-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, Making trades, Withdrawals, etc.

Subdomain takeover with already-connected wallet interaction

Direct theft of user funds

Malicious interactions with an already-connected wallet, such as:  Modifying transaction arguments or parameters, Substituting contract addresses, Submitting malicious transactions

0x Source code

0x Documentation

Rewards are distributed according to the impact of the vulnerability based on the [Immunefi Vulnerability Severity Classification System V2.3. ](https://immunefi.com/immunefi-vulnerability-severity-classification-system-v2-3/)

__Reward Calculation for Critical Level Reports__

For critical smart contract bugs, the reward amount is 10% of the funds directly affected up to a maximum of USD 1 000 000. The calculation of the amount of funds at risk is based on the time and date the bug report is submitted. However, a minimum reward of USD 100 000 is to be rewarded in order to incentivize security researchers against withholding a critical bug report.

Only the impact of direct theft of user funds **at-rest** is eligible for the maximum payout of USD 1 000 000; all other Critical-level smart contract reports are eligible for a maximum payout of USD 500 000.


__Repeatable Attack Limitations__

If the smart contract where the vulnerability exists can be upgraded or paused, only the initial attack will be considered for a reward. This is because the project can mitigate the risk of further exploitation by upgrading or pausing the component where the vulnerability exists. The reward amount will depend on the severity of the impact and the funds at risk. 

For critical repeatable attacks on smart contracts that cannot be upgraded or paused, the project will consider the cumulative impact of the repeatable attacks for a reward. This is because the project cannot prevent the attacker from repeatedly exploiting the vulnerability until all funds are drained and/or other irreversible damage is done. Therefore, this warrants a reward equivalent to 10% of funds at risk, capped at the maximum critical reward. 

__Reward Calculation for High Level Reports__

High vulnerabilities concerning theft/permanent freezing of unclaimed yield/royalties are rewarded within a range of USD 35 000 to USD 100 000 depending on the funds at risk, capped at the maximum high reward. 

In the event of temporary freezing, the reward doubles from the full frozen value for every additional [24h] that the funds are temporarily frozen, up until a max cap of the high reward. This is because as the duration of the freezing lengthens, the potential for greater damage and subsequent reputational harm intensifies. Thus, by increasing the reward proportionally with the frozen duration, the project ensures stronger incentives for bug disclosure of this nature.

For critical web/apps bug reports will be rewarded with USD 50 000, only if the impact leads to:

- A loss of funds involving an attack that does not require any user action
- Malicious interactions with an already-connected wallet
- Private key or private key generation leakage leading to unauthorized access to user funds 

All other impacts that would be classified as Critical would be rewarded a flat amount of USD 15 000. The rest of the severity levels are paid out according to the Impact in Scope table.  

__Reward Payment Terms__

Payouts are handled by the 0x team directly and are denominated in USD. However, payments are done in USDC on Ethereum.

Title	Description	Link
0x Documentation	Program Documentation
0x Documentation	Further Documentation

0x

Codebase

Documentation