Magic Block - Delegation Program - Magic Block

1. Introduction

Magic Block engaged Halborn to conduct a security assessment on their Delegation Solana program beginning on March 10th, 2025, and ending on March 28th, 2025. The security assessment was scoped to the Solana program provided in magicblock-labs/delegation-program GitHub repository. Commit hashes and further details can be found in the Scope section of this report.

This Delegation Program lets Solana smart contracts hand off their PDAs to an off-chain “ephemeral rollup” for fast updates. While delegated, the program enforces ownership locks and tracks changes, then finalizes them on-chain so the mainnet state stays consistent.

It supports creating ephemeral balances (temporary escrow accounts), delegating/undelegating program accounts, committing off-chain data, and finalizing rollup results. Fees are handled through two vaults—one for protocol fees and one for each validator’s fees—both governed by an admin or the program upgrade authority.

This design gives high-throughput advantages without compromising on Solana’s security model, enabling dApps to scale off-chain while retaining the trust guarantees and atomic settlement of L1.

2. Assessment Summary

Halborn was provided 15 days for the engagement and assigned one full-time security engineer to review the security of the Solana Program in scope. The engineer is a blockchain and smart contract security expert with advanced smart contract hacking skills, and deep knowledge of multiple blockchain protocols.

The purpose of the assessment is to:

• Identify potential security issues within the Delegation Solana Program.

• Ensure that the program's functionality operates as intended.

  
  

In summary, Halborn identified some improvements to reduce the likelihood and impact of risks, which were addressed or acknowledged by the Magic Block team: 

• Consider using a multi-signature wallet or multi-step upgradeable authority approach for enhanced resilience. Additionally, store the admin key in a config account that can be updated, rather than hard-coding a Pubkey as a protocol constant.

• Implement robust verification logic in verify.rs (e.g., cryptographic proof checks, signature validations, or protocol invariants). Additionally, remove the TODO placeholder once real checks are in place. Ensure the function fails if the new state data is malformed or violates any business-critical constraints.

• Add an authorization check so only a recognized admin or multi-signature wallet can create the protocol fees vault.

3. Test Approach and Methodology

Halborn performed a combination of a manual review of the source code and automated security testing to balance efficiency, timeliness, practicality, and accuracy in regard to the scope of the program assessment. While manual testing is recommended to uncover flaws in business logic, processes, and implementation; automated testing techniques help enhance coverage of programs and can quickly identify items that do not follow security best practices.

The following phases and associated tools were used throughout the term of the assessment:

• Research into the architecture, purpose, and use of the platform.

• Manual program source code review to identify business logic issues.

• Mapping out possible attack vectors.

• Thorough assessment of safety and usage of critical Rust variables and functions in scope that could lead to arithmetic vulnerabilities.

• Scanning dependencies for known vulnerabilities (cargo audit).

• Local runtime testing (solana-test-framework).