Smart Contract Assessment Audit | 1win

Summary

100% of all REPORTED Findings have been addressed

About this report

Assessment Type

Assurance Assessment

Date of Engagement

August 20th, 2026 - August 31st, 2026

Source Code

1win-token-solana-programs

Assessed Commit ID

a07375d

Severity Breakdown

0Risk Accepted
1Partially Solved
3Solved
4All Findings

Critical0
High0
Medium1
- 1Solved
Low2
- 1P. Solved
- 1Solved
Informational1
- 1Solved

Summary#

Introduction#

1Win engaged Halborn to conduct a security assessment on their smart contracts beginning on August 20th, 2026 and ending on August 31st, 2026. The security assessment was scoped to the repository listed with commit hash, and further details in the Scope section of this report.

Assessment Summary#

The team at Halborn assigned a full-time security engineer to assess 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 issues with the smart contracts.

In summary, Halborn identified some improvements to reduce the likelihood and impact of risks, which were mostly addressed by the 1Win team. The main ones were the following:

Ensure that all token burns are executed exclusively through the program and subject to its configured limits.
Enforce reasonable minimum durations for all participation windows.
Provide a recovery path that allows a future claim window to be scheduled when the original activation deadline has expired.

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 (anchor test)

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.

5.1 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 ( $m_e$ )	METRIC VALUE	NUMERICAL VALUE
Attack Origin (AO)	Arbitrary (AO:A)	1
Attack Origin (AO)	Specific (AO:S)	0.2
Attack Cost (AC)	Low (AC:L)	1
	Medium (AC:M)	0.67
	High (AC:H)	0.33
Attack Complexity (AX)	Low (AX:L)	1
	Medium (AX:M)	0.67
	High (AX:H)	0.33

Exploitability

E

is calculated using the following formula:

$E = \prod m_e$

5.2 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 ( $m_I$ )	METRIC VALUE	NUMERICAL VALUE
Confidentiality (C)	None (C:N)	0
	Low (C:L)	0.25
	Medium (C:M)	0.5
	High (C:H)	0.75
	Critical (C:C)	1
Integrity (I)	None (I:N)	0
	Low (I:L)	0.25
	Medium (I:M)	0.5
	High (I:H)	0.75
	Critical (I:C)	1
Availability (A)	None (A:N)	0
	Low (A:L)	0.25
	Medium (A:M)	0.5
	High (A:H)	0.75
	Critical (A:C)	1
Deposit (D)	None (D:N)	0
	Low (D:L)	0.25
	Medium (D:M)	0.5
	High (D:H)	0.75
	Critical (D:C)	1
Yield (Y)	None (Y:N)	0
	Low (Y:L)	0.25
	Medium (Y:M)	0.5
	High (Y:H)	0.75
	Critical (Y:C)	1

Impact

I

is calculated using the following formula:

$I = max(m_I) + \frac{\sum{m_I} - max(m_I)}{4}$

5.3 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 ( $C$ )	COEFFICIENT VALUE	NUMERICAL VALUE
Reversibility ( $r$ )	None (R:N)	1
	Partial (R:P)	0.5
	Full (R:F)	0.25
Scope ( $s$ )	Changed (S:C)	1.25
Scope ( $s$ )	Unchanged (S:U)	1

Severity Coefficient

C

is obtained by the following product:

$C = rs$

The Vulnerability Severity Score

S

is obtained by:

$S = min(10, EIC * 10)$

The score is rounded up to 1 decimal places.

Critical	High	Medium	Low	Informational
9 - 10	7 - 8.9	4.5 - 6.9	2 - 4.4	0 - 1.9

Scope#

(a) Repository:1win-token-solana-programs

(b) Assessed Commit ID:a07375d94377e9db6e991e0f5c9ac862a5cbc583

58 files

1win-token-solana-programs / programs

58 files

burn

13 files

src

12 files

instructions

5 files

burn.rs

rust

initialize.rs

rust

mod.rs

rust

params.rs

rust

roles.rs

rust

state

3 files

burn_counters.rs

rust

burn_state.rs

rust

Out-of-Scope:Third party dependencies and economic attacks.

26c8ca588e31c528910ba93c1f4314800bf573bf 08080082e0252632dc387a903d1f361cca25e132 e4d921e53de1e12f0da38ce3cb439a504fc3ce62 032abd4a4e73503cd89f6cd8c3d33bed9c9cfb2b

Out-of-Scope: New features/implementations after the remediation commit IDs.

Assessment Summary & Findings Overview#

#	Title	Severity	Score	Status
HAL-01	Direct token authority bypasses burn controls	Medium	5.0	Solved09/16/2026
HAL-02	Participation windows can be configured with unusable durations	Low	3.4	Partially Solved09/16/2026
HAL-03	Claim activation can become permanently unavailable after the scheduling window expires	Low	3.4	Solved09/16/2026
HAL-04	Recipient assignments can make vested tokens permanently inaccessible	Informational	1.6	Solved09/16/2026

Findings & Tech Details#

HAL-01Solved

Direct token authority bypasses burn controls

Medium

5.0AO:A/AC:L/AX:M/R:N/S:U/C:N/A:N/I:H/D:N/Y:NAO:A/AC:L/AX:M/R:N/S:U/C:N/A:N/I:H/D:N/Y:N

Description

Proof of Concept

Recommendation

Remediation Comment

Addressed in:

26c8ca588e31c528910ba93c1f4314800bf573bf

HAL-02Partially Solved

Participation windows can be configured with unusable durations

Low

3.4AO:A/AC:L/AX:M/R:N/S:U/C:N/A:N/I:N/D:M/Y:NAO:A/AC:L/AX:M/R:N/S:U/C:N/A:N/I:N/D:M/Y:N

Description

Recommendation

Remediation Comment

Addressed in:

08080082e0252632dc387a903d1f361cca25e132

HAL-03Solved

Claim activation can become permanently unavailable after the scheduling window expires

Low

3.4AO:A/AC:L/AX:M/R:N/S:U/C:N/A:M/I:N/D:N/Y:NAO:A/AC:L/AX:M/R:N/S:U/C:N/A:M/I:N/D:N/Y:N

Description

Recommendation

Remediation Comment

Addressed in:

e4d921e53de1e12f0da38ce3cb439a504fc3ce62

HAL-04Solved

Recipient assignments can make vested tokens permanently inaccessible

Informational

1.6AO:A/AC:L/AX:H/R:N/S:U/C:N/A:M/I:N/D:N/Y:NAO:A/AC:L/AX:H/R:N/S:U/C:N/A:M/I:N/D:N/Y:N

Description

Recommendation

Remediation Comment

Addressed in:

032abd4a4e73503cd89f6cd8c3d33bed9c9cfb2b

Disclaimer#

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.