Prepared by:
HALBORN
Last Updated 09/04/2025
Date of Engagement: July 1st, 2025 - July 9th, 2025
100% of all REPORTED Findings have been addressed
All findings
11
Critical
0
High
0
Medium
0
Low
2
Informational
9
Taurus engaged Halborn to perform a security assessment of their smart contracts from July 1st, 2025, to July 9th, 2025. The assessment scope was limited to the smart contracts provided to Halborn. Commit hashes and additional details are available in the Scope section of this report.
The Taurus codebase in scope consists of a Solidity implementation of the CMTAT security token framework, featuring modular compliance and technical capabilities for regulated financial assets on EVM-compatible blockchains, featuring compliance controls and upgradeability.
Halborn was allocated 7 days for this engagement and assigned 1 full-time security engineer to conduct a comprehensive review of the smart contracts within scope. The engineer is an expert in blockchain and smart contract security, with advanced skills in penetration testing and smart contract exploitation, as well as extensive knowledge of multiple blockchain protocols.
The objectives of this assessment were to:
Identify potential security vulnerabilities within the smart contracts.
Verify that the smart contract functionality operates as intended.
In summary, Halborn identified several areas for improvement to reduce the likelihood and impact of potential risks, which were partially addressed by the Taurus team. The primary recommendations were as follows:
Modify the _canMintBurnByModule() function to respect the paused state.
Modify the _forcedTransfer() function to handle allowances in a safe and predictable manner.
Lock the pragma version to the same version used during development and testing.
Halborn conducted a combination of manual code review and automated security testing to balance efficiency, timeliness, practicality, and accuracy within the scope of this assessment. While manual testing is crucial for identifying flaws in logic, processes, and implementation, automated testing enhances coverage of smart contracts and quickly detects deviations from established security best practices.
The following phases and associated tools were employed throughout the term of the assessment:
Research into the platform's architecture, purpose and use.
Manual code review and walkthrough of smart contracts to identify any logical issues.
Comprehensive assessment of the safety and usage of critical Solidity variables and functions within scope that could lead to arithmetic-related vulnerabilities.
Local testing using custom scripts (Foundry).
Fork testing against main networks (Foundry).
Static security analysis of scoped contracts, and imported functions (Slither).
After the initial assessment, Taurus reported an additional compliance issue affecting batch operations. Halborn performed a post-assessment review at commit 198d019 to verify the fixes, and confirmed that the issue has been addressed at that commit.
| EXPLOITABILITY METRIC () | METRIC VALUE | NUMERICAL 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 |
| IMPACT METRIC () | METRIC VALUE | NUMERICAL 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 |
| SEVERITY COEFFICIENT () | COEFFICIENT VALUE | NUMERICAL VALUE |
|---|---|---|
| Reversibility () | None (R:N) Partial (R:P) Full (R:F) | 1 0.5 0.25 |
| Scope () | Changed (S:C) Unchanged (S:U) | 1.25 1 |
| Severity | Score Value Range |
|---|---|
| Critical | 9 - 10 |
| High | 7 - 8.9 |
| Medium | 4.5 - 6.9 |
| Low | 2 - 4.4 |
| Informational | 0 - 1.9 |
Critical
0
High
0
Medium
0
Low
2
Informational
9
| Security analysis | Risk level | Remediation Date |
|---|---|---|
| Minting and burning operations bypass the pause mechanism | Low | Future Release - 07/16/2025 |
| Insufficient allowance validation during forced transfers | Low | Risk Accepted - 07/16/2025 |
| Floating pragma | Informational | Acknowledged - 07/16/2025 |
| Misleading restriction code returned for deactivated contract | Informational | Solved - 07/16/2025 |
| Commented functionality | Informational | Solved - 07/16/2025 |
| Typos | Informational | Solved - 07/16/2025 |
| Public functions not called within contracts | Informational | Acknowledged - 07/16/2025 |
| Misleading comment regarding frozen balance calculation | Informational | Solved - 07/16/2025 |
| Inconsistent method of calling inherited functions | Informational | Solved - 07/16/2025 |
| Lack of named mappings | Informational | Solved - 07/16/2025 |
| Unused file | Informational | Acknowledged - 07/16/2025 |
//Low
//Low
//Informational
//Informational
//Informational
//Informational
//Informational
//Informational
//Informational
//Informational
//Informational
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
CMTAT
* Use Google Chrome for best results
** Check "Background Graphics" in the print settings if needed
