Ripple - Smart Contract Audit - Credentials - Ripple

1. Introduction

Ripple engaged Halborn to conduct a security assessment on XRP Ledger (XRPL) feature amendments beginning on January 6th, 2025 and ending on January 30th, 2025, focusing on modifications to the codebase between the commit 4c2e6a3 and the commit cd9b5c9. The review specifically targets changes introduced during these commits, assuming the validity of the pre-existing logic and excluding verification of its security, e.g., input validation of previously existing parameters.

The Credentials feature introduced new transaction validation mechanisms and structures that allow credential-based authorization within the Ripple network. This feature enables accounts to issue, manage, and verify credentials for transaction approval, adding an additional layer of security and control.

2. Assessment Summary

The team at Halborn assigned a full-time security engineer to assess the security of the node. The security engineer is a blockchain and smart-contract security expert in advanced penetration testing, smart-contract hacking, and deep knowledge of multiple blockchain protocols.

The purpose of this assessment is to:

• Ensure that the new features operate as intended.

• Identify potential security issues with the new features.

In summary, Halborn identified some improvements to reduce the likelihood and impact of risks, which were mostly acknowledged by the Ripple team. The main ones were the following: 

• Ensure that expired NFT offers and credentials are handled separately by using distinct error codes.

• Explicitly reject transactions signed with a disabled Master Key, even if it is also set as the Regular Key.

• Replace assertions with explicit error handling that operates in all build configurations.

• Include a check that confirms whether the recipient has configured Deposit Auth before invoking verifyDepositPreauth.

3. Test Approach and Methodology

Halborn performed a combination of manual review of the code and automated security testing to balance efficiency, timeliness, practicality, and accuracy in regard to the scope of the node security assessment. While manual testing is recommended to uncover flaws in logic, process, and implementation; automated testing techniques help enhance coverage 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 code review and walkthrough to identify any logic issue.

• Graphing out functionality and contract logic/connectivity/functions.