← Back to Audits

Credit Accounts - THORChain

Prepared by:

Halborn Logo

HALBORN

Last Updated 12/08/2025

Date of Engagement: October 29th, 2025 - November 3rd, 2025

Summary

100% of all REPORTED Findings have been addressed

All findings

7

Critical

0

High

0

Medium

2

Low

2

Informational

3

Table of Contents

1. Introduction

THORChain engaged Halborn to conduct a security assessment of the Ghost Credit contracts, beginning on October 29th, 2025 and ending on November 4th, 2025. This security assessment was scoped to the CosmWasm smart contracts in the Rujira Ghost repository. Commit hashes and further details can be found in the Sources section of this report.


Ghost Credit is a decentralized credit module designed for the Rujira ecosystem. It enables users to create self-custodied credit accounts that interact with mapped Ghost Vault markets to borrow and repay assets against on-chain collateral. The system enforces per-account Loan-to-Value (LTV) ratios, supports permissionless liquidations with bounded over-liquidation windows, and integrates liquidation preferences to determine the order of collateral consumption. The contracts are implemented in Rust using CosmWasm and operate over THOR chain.

2. Assessment Summary

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

The purpose of this assessment is to:

    • Ensure that smart-contract functions operate as intended

    • Identify potential security and logic issues within the contract implementation


In summary, Halborn identified several improvements to reduce the likelihood and impact of operational and financial risks, which were partially addressed by the Rujira team. The main ones were the following:

    • Refactor liquidation validation to separate collateral and debt sets, ignore debt-denom increases, and compute slippage in USD value with oracle pricing.

    • Treat “Account Safe” (LTV below adjustment threshold) as a successful liquidation outcome or remove the unnecessary unsafe check from the liquidation path.

    • Validate liquidation preferences on save to reject cycles, self-references, and invalid or non-whitelisted denoms, and ensure acyclic dependency enforcement.

    • Add strict configuration validation enforcing coherent thresholds, fee sums below 1, valid liquidation windows, and consistent parameter ranges on every update.

    • Enforce cross-validation in SetVault and SetCollateral ensuring ratios are in [0,1], borrow denoms are whitelisted, and mappings remain consistent under governance updates.

    • Guard LTV calculations against division-by-zero and rounding errors by returning safe sentinel values and performing conservative comparisons in post-checks.


3. Test Approach and Methodology

Halborn performed a combination of manual and automated security testing to ensure coverage and precision throughout this assessment. Manual review focused on business logic, inter-contract interactions, and edge-case validation, while automated tooling was used to detect known vulnerability classes and dependency risks. The following phases and techniques were used during the audit:

    • Research into the architecture, purpose, and integration with Ghost Vault contracts.

    • Manual line-by-line code review and walkthrough of all CosmWasm modules in scope.

    • Manual assessment of critical functions to detect arithmetic and logical vulnerabilities.

    • Evaluation of post-check atomicity and liquidation invariants.

    • Verification of authorization boundaries and sudo/admin safety.

    • Review of cross-contract calls to external vaults and potential DoS vectors.

    • Automated static analysis using cargo audit and other Rust-specific scanning tools.

    • Review and verification of integration and multi-test scenarios for borrow/repay/liquidation flows.


4. RISK METHODOLOGY

Every vulnerability and issue observed by Halborn is ranked based on two sets of Metrics and a Severity Coefficient. This system is inspired by the industry standard Common Vulnerability Scoring System.
The two Metric sets are: Exploitability and Impact. Exploitability captures the ease and technical means by which vulnerabilities can be exploited and Impact describes the consequences of a successful exploit.
The Severity Coefficients is designed to further refine the accuracy of the ranking with two factors: Reversibility and Scope. These capture the impact of the vulnerability on the environment as well as the number of users and smart contracts affected.
The final score is a value between 0-10 rounded up to 1 decimal place and 10 corresponding to the highest security risk. This provides an objective and accurate rating of the severity of security vulnerabilities in smart contracts.
The system is designed to assist in identifying and prioritizing vulnerabilities based on their level of risk to address the most critical issues in a timely manner.

4.1 EXPLOITABILITY

Attack Origin (AO):
Captures whether the attack requires compromising a specific account.
Attack Cost (AC):
Captures the cost of exploiting the vulnerability incurred by the attacker relative to sending a single transaction on the relevant blockchain. Includes but is not limited to financial and computational cost.
Attack Complexity (AX):
Describes the conditions beyond the attacker’s control that must exist in order to exploit the vulnerability. Includes but is not limited to macro situation, available third-party liquidity and regulatory challenges.
Metrics:
EXPLOITABILITY METRIC (mem_e)METRIC VALUENUMERICAL VALUE
Attack Origin (AO)Arbitrary (AO:A)
Specific (AO:S)		1
0.2
Attack Cost (AC)Low (AC:L)
Medium (AC:M)
High (AC:H)		1
0.67
0.33
Attack Complexity (AX)Low (AX:L)
Medium (AX:M)
High (AX:H)		1
0.67
0.33
Exploitability EE is calculated using the following formula:

E=∏meE = \prod m_e

4.2 IMPACT

Confidentiality (C):
Measures the impact to the confidentiality of the information resources managed by the contract due to a successfully exploited vulnerability. Confidentiality refers to limiting access to authorized users only.
Integrity (I):
Measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of data stored and/or processed on-chain. Integrity impact directly affecting Deposit or Yield records is excluded.
Availability (A):
Measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability. This metric refers to smart contract features and functionality, not state. Availability impact directly affecting Deposit or Yield is excluded.
Deposit (D):
Measures the impact to the deposits made to the contract by either users or owners.
Yield (Y):
Measures the impact to the yield generated by the contract for either users or owners.
Metrics:
IMPACT METRIC (mIm_I)METRIC VALUENUMERICAL VALUE
Confidentiality (C)None (C:N)
Low (C:L)
Medium (C:M)
High (C:H)
Critical (C:C)		0
0.25
0.5
0.75
1
Integrity (I)None (I:N)
Low (I:L)
Medium (I:M)
High (I:H)
Critical (I:C)		0
0.25
0.5
0.75
1
Availability (A)None (A:N)
Low (A:L)
Medium (A:M)
High (A:H)
Critical (A:C)		0
0.25
0.5
0.75
1
Deposit (D)None (D:N)
Low (D:L)
Medium (D:M)
High (D:H)
Critical (D:C)		0
0.25
0.5
0.75
1
Yield (Y)None (Y:N)
Low (Y:L)
Medium (Y:M)
High (Y:H)
Critical (Y:C)		0
0.25
0.5
0.75
1
Impact II is calculated using the following formula:

I=max(mI)+∑mI−max(mI)4I = max(m_I) + \frac{\sum{m_I} - max(m_I)}{4}

4.3 SEVERITY COEFFICIENT

Reversibility (R):
Describes the share of the exploited vulnerability effects that can be reversed. For upgradeable contracts, assume the contract private key is available.
Scope (S):
Captures whether a vulnerability in one vulnerable contract impacts resources in other contracts.
Metrics:
SEVERITY COEFFICIENT (CC)COEFFICIENT VALUENUMERICAL VALUE
Reversibility (rr)None (R:N)
Partial (R:P)
Full (R:F)		1
0.5
0.25
Scope (ss)Changed (S:C)
Unchanged (S:U)		1.25
1
Severity Coefficient CC is obtained by the following product:

C=rsC = rs

The Vulnerability Severity Score SS is obtained by:

S=min(10,EIC∗10)S = min(10, EIC * 10)

The score is rounded up to 1 decimal places.
SeverityScore Value Range
Critical9 - 10
High7 - 8.9
Medium4.5 - 6.9
Low2 - 4.4
Informational0 - 1.9

5. SCOPE

REPOSITORY
(a) Repository: rujira
(b) Assessed Commit ID: 9989bb5
(c) Items in scope:
  • contracts/rujira-ghost-credit/src/events.rs
  • contracts/rujira-ghost-credit/src/error.rs
  • contracts/rujira-ghost-credit/src/config.rs
↓ Expand ↓
Out-of-Scope: Third party dependencies and economic attacks.
Remediation Commit ID:
Out-of-Scope: New features/implementations after the remediation commit IDs.

6. Assessment Summary & Findings Overview

Critical

0

High

0

Medium

2

Low

2

Informational

3

Security analysisRisk levelRemediation Date
Conflicting liquidation checks allow Denial of ServiceMediumSolved - 11/24/2025
Liquidation DoS when final LTV drops below adjustment_thresholdMediumNot Applicable - 11/28/2025
Missing validation for liquidation preferencesLowSolved - 11/24/2025
Missing enforcement of critical configuration invariantsLowSolved - 11/24/2025
Missing validation in SetVault and SetCollateralInformationalSolved - 11/24/2025
Division-by-zero in adjusted LTVInformationalAcknowledged - 11/28/2025
Missing Repay message allows incomplete settlement flowInformationalAcknowledged

7. Findings & Tech Details

7.1 Conflicting liquidation checks allow Denial of Service

//

Medium

Description
Proof of Concept
BVSS
Recommendation
Remediation Comment
Remediation Hash
https://gitlab.com/thorchain/rujira/-/commit/1f6cce711b0245c13222fbc773000d650cc9536c

7.2 Liquidation DoS when final LTV drops below adjustment_threshold

//

Medium

Description
Proof of Concept
BVSS
Recommendation
Remediation Comment

7.3 Missing validation for liquidation preferences

//

Low

Description
BVSS
Recommendation
Remediation Comment
Remediation Hash
https://gitlab.com/thorchain/rujira/-/commit/beaf062d0c964fe59d69af23ffeb9c2109a63971

7.4 Missing enforcement of critical configuration invariants

//

Low

Description
BVSS
Recommendation
Remediation Comment
Remediation Hash
https://gitlab.com/thorchain/rujira/-/commit/ed05d6fa8830949e1d171383af700857a2540fb0

7.5 Missing validation in SetVault and SetCollateral

//

Informational

Description
BVSS
Recommendation
Remediation Comment
Remediation Hash
https://gitlab.com/thorchain/rujira/-/commit/07bf1750944c10c238e0ffe5e2ab3310d6525b7e

7.6 Division-by-zero in adjusted LTV

//

Informational

Description
BVSS
Recommendation
Remediation Comment

7.7 Missing Repay message allows incomplete settlement flow

//

Informational

Description
Score
(0.0)
Recommendation
Remediation Comment

Halborn strongly recommends conducting a follow-up assessment of the project either within six months or immediately following any material changes to the codebase, whichever comes first. This approach is crucial for maintaining the project’s integrity and addressing potential vulnerabilities introduced by code modifications.

// Download the full report

Credit Accounts

* Use Google Chrome for best results

** Check "Background Graphics" in the print settings if needed