ZKsync OS

ZKsync OS is an efficient, modular blockchain execution layer that enables chains to run different virtual machines, such as EVM, EraVM, or WASM. Currently, only the EVM is supported. The ZKsync OS program is designed to be compiled to RISC-V, with ZKsync Airbender used to prove the execution of this RISC-V program.

Airbender is ZKsync’s next-generation proof system, purpose-built to enable efficient zero-knowledge proofs of RISC-V bytecode execution. Built on highly optimized STARK/FRI implementations, Airbender is designed to support ZKsync’s long-term scaling strategy by being fast, cost-efficient, and adaptable to a wide range of use cases — without compromising security.

As a promotional event to attract more security researchers, the ZKsync team has intentionally included a bug in their codebase that would lead to a Medium-level impact according to the Impacts in Scope section. The ZKsync team has committed to paying the first valid report on this impact, and agrees to waive the known issue rejection rights for it, including if the security researcher finds a higher level impact than intended.

For more information about ZKsync OS, please visit https://www.zksync.io/.

ZKsync OS provides rewards in USDC on ZKsync Era, denominated in USD. For more details about the payment process, please view the Rewards by Threat Level section.

KYC Requirement

ZKsync OS will be requesting KYC information in order to pay for successful bug submissions.

Eligibility Criteria Security researchers who wish to participate must adhere to the rules of engagement set forth in this program and cannot be:

• On OFACs SDN list
• Official contributor, both past or present
• Employees and/or individuals closely associated with the project
• Security auditors that directly or indirectly participated in the audit review

Responsible Publication

ZKsync OS adheres to Category 3: Approval Required. This Policy determines what information researchers are allowed to make public from their submitted bug reports. For more information about the category selected, please refer to our Responsible Publication page.

Primacy of Impact vs Primacy of Rules

ZKsync OS adheres to the Primacy of Impact for the following impacts:

• Blockchain/DLT — Critical
• Blockchain/DLT — High
• Blockchain/DLT — Medium

Primacy of Impact means that the impact is prioritized rather than a specific asset. This encourages security researchers to report on all bugs with an in-scope impact, even if the affected assets are not in scope.

For more information, please see Best Practices: Primacy of Impact

When submitting a report on Immunefi’s dashboard, the security researcher should select the Primacy of Impact asset placeholder. If the team behind this project has multiple programs, those other programs are not covered under Primacy of Impact for this program. Instead, check if those other projects have a bug bounty program on Immunefi.

If the project has any testnet and/or mock files, those will not be covered under Primacy of Impact. All other impacts are considered under the Primacy of Rules, which means that they are bound by the terms and conditions set within this program.

Proof of Concept (PoC) Requirements

A PoC, demonstrating the bug's impact, is required for this program and has to comply with the Immunefi PoC Guidelines and Rules.

Public Disclosure of Known Issues

Bug reports covering previously-discovered bugs (listed below) are not eligible for a reward within this program. This includes known issues that the project is aware of but has consciously decided not to “fix”, necessary code changes, or any implemented operational mitigating procedures that can lessen potential risk.

Previous Audits

ZKsync OS’s completed audit reports can be found at https://docs.zksync.io/zksync-protocol/security/audits. Any unfixed vulnerabilities mentioned in these reports are not eligible for a reward.

Feasibility Limitations

The project may be receiving reports that are valid (the bug and attack vector are real) and cite assets and impacts that are in scope, but there may be obstacles or barriers to executing the attack in the real world. In other words, there is a question about how feasible the attack really is. Conversely, there may also be mitigation measures that projects can take to prevent the impact of the bug, which are not feasible or would require unconventional action and hence, should not be used as reasons for downgrading a bug's severity.

Therefore, Immunefi has developed a set of feasibility limitation standards which by default states what security researchers, as well as projects, can or cannot cite when reviewing a bug report.

Issues that can be effectively mitigated by security measures such as a consistency checker and/or realistic, authorized actions by the Security Council will be considered lower impact than vulnerabilities that would cause irreparable or irreversible harm, and thus will be downgraded or classified as out of scope, at the discretion of ZkSync. A maximum possible payout for a Critical severity submission is only possible in cases where special access is not required to steal or permanently freeze funds (freezing funds with no way to restore them other than a hard fork).