L1ERC20Bridge proxy TransparentUpgradeableProxy.sol

- __Smart Contracts - PoC__, Smart Contract bug reports are to include a runnable Proof of Concept (PoC) in order to prove impact.  
- For more information on PoCs please visit: [Proof of Concept (PoC) Guidelines and Rules.](https://immunefisupport.zendesk.com/hc/en-us/articles/9946217628561-Proof-of-Concept-PoC-Guidelines-and-Rules)

- __Web/App__ - Bug reports are to include a runnable Proof of Concept (PoC) in order to prove impact. All web/app bug reports must come with a PoC with an end-effect impacting an asset-in-scope in order to be considered for a reward. All PoC content must adhere to the [PoC guidelines and rules of Immunefi](https://immunefisupport.zendesk.com/hc/en-us/articles/9946217628561-Proof-of-Concept-PoC-Guidelines-and-Rules). In the event that a PoC requires an attack on a web/app asset provided, they must still adhere to the rules provided, otherwise eligibility for a reward may be revoked. 

- For more information on PoCs please visit: [Proof of Concept (PoC) Guidelines and Rules](https://immunefisupport.zendesk.com/hc/en-us/articles/9946217628561-Proof-of-Concept-PoC-Guidelines-and-Rules)

Whitehats we highly encourage you to review any potential subdomains and what specific port(s) are in scope. Even though the domain may be the same, different ports may point to different assets.  

__Dev Environment and Documentation:__

ZKsync has included dev documentation and/or instructions to help in reviewing code and exploring for bugs:

- [https://github.com/matter-labs/zksync-era](https://github.com/matter-labs/zksync-era)
- [https://github.com/matter-labs/era-contracts](https://github.com/matter-labs/era-contracts)
- [https://github.com/matter-labs/era-zkevm_circuits](https://github.com/matter-labs/era-zkevm_circuits)
- [https://github.com/matter-labs/era-zkevm_opcode_defs](https://github.com/matter-labs/era-zkevm_opcode_defs)
- [https://github.com/matter-labs/era-zkEVM-assembly](https://github.com/matter-labs/era-zkEVM-assembly)
- [https://github.com/matter-labs/era-zkevm_test_harness](https://github.com/matter-labs/era-zkevm_test_harness)
- [https://github.com/matter-labs/era-zk_evm](https://github.com/matter-labs/era-zk_evm)

__Impacts to other assets:__

Hackers are encouraged to submit issues outside of the outlined Impacts and Assets in Scope. 

If whitehats can demonstrate a critical and high impact for an asset not in scope, ZKsync encourages you to submit your bug report using the “primacy of impact exception” asset.

ZKsync Era is a layer 2 rollup that uses zero-knowledge proofs to scale Ethereum without compromising on security or decentralization. Since it's EVM compatible (Solidity/Vyper), 99% of Ethereum projects can redeploy without refactoring or re-auditing a single line of code.

Contract fails to deliver promised returns, but doesn't lose value

Permanent freezing of funds (that can be fixed by upgrade)

Permanent stopping the priority queue

Theft of user fees

Contract verification bypass

Misrepresentation of the transaction data that may lead to misleading third party users (e.g. manipulating transaction event log representation, transfer amount, etc)

Misrepresentation of the transaction data that may lead to misleading API users (e.g. manipulating transaction event log representation, transfer amount, etc)

Difference between implementation outside of the circuit and within the circuit, where the in-circuit implementation is accurate (e.g. overconstraint in the circuit)

Block stuffing for profit

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

Theft of gas

Unbounded gas consumption

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

Permanent freezing of funds (that cannot be fixed by upgrade)

Protocol insolvency

Execute arbitrary system commands

Retrieve sensitive data/files from a running server such as: database passwords, blockchain keys, etc (this does not include non-sensitive environment variables, open source code, or usernames)

Taking down the application/website

Direct loss of funds

__Reward Distribution:__

Please review how rewards are distributed based on the [Immunefi Vulnerability Severity Classification System V2.2.](https://immunefi.com/immunefi-vulnerability-severity-classification-system-v2-2/) This is a simplified 5-level scale system with separate scales for Smart Contracts and Websites/Apps.

__Payouts and Payout Requirements:__

Rewards for critical smart contract bug reports will be further capped at 10% of direct funds at risk based on the PoC provided.. However, there is a minimum reward of __USD 100 000__.

For the project's bug bounty program, high-severity smart contract vulnerability rewards are determined according to an internal set of criteria established by the team. These criteria take into account the exploitability, impact, and probability of the vulnerability occurring, with special consideration given to bug reports that require multiple conditions not currently in place. There is a minimum reward of __USD 20,000__ for high-severity level vulnerabilities, and the maximum reward is capped at 100% of the affected funds, up to the max high cap, whichever is lower.

Payouts are handled by the ZKsync team directly and are denominated in USD. However, payouts are done in USDC (ZKsync Era). ZKsync commits to honoring payouts according to the terms set out in this program at the time of report submission, and to treat this program as the agreement and source of truth concerning bug reports and responsible disclosures. 

For the purposes of determining report validity, this is a Primacy of Impact program. 

Learn more about report validity best practices here: [Best Practice - Primacy of Impact vs Primacy of Rules. ](https://immunefisupport.zendesk.com/hc/en-us/articles/12340245635089-Best-Practices-Primacy-of-Impact)

__KYC Requirements:__

zkSync Era has a Know Your Customer (KYC) requirement for bug bounty payouts. Government identification is required for the KYC process.


__Known Issue Assurance__

ZKsync Era commits to providing Known Issue Assurance to bug submissions through their program. This means that ZKsync Era will either disclose known issues publicly, or at the very least, privately via a self-reported bug submission. 

In a potential scenario of a mediation, this allows for a more objective and streamlined process, in order to prove that an issue is known. Otherwise, assuming the bug report is valid, it would result in the report being considered as in-scope, and due a reward.

__Audit Discoveries and Known Issues:__

Bug reports covering previously-discovered bugs are not eligible for any reward through the bug bounty program. If a bug report covers a known issue, it may be rejected together with proof of the issue being known before escalation of the bug report via Immunefi. 

Previous audits and known issues can be found at:
- [https://docs.zksync.io/build/resources/audit-bug-bounty#audits](https://docs.zksync.io/build/resources/audit-bug-bounty#audits)
A separate note on the fee model: ZKsync has different gas prices per opcodes than Ethereum. Also, it is known that since gasPerPubdataByte is fluctuating, it may lead for gasLimits to not be reliable in the middle/long-term. 

The fee model is still in development and so the operator may not be fully compensated. The impact of griefing attacks will be evaluated based on the ratio between funds spent by the attacker and the funds spent by the operator.

ZKsync era