Nexo Token (NEXO) security audit, conducted by the Callisto Network Security Department in June 2019.


Nexo (NEXO) Specificities




Audit Request

Audit Top 200 CoinMarketCap tokens.

Symbol      : NEXO
Name        : NEXO

Nexo is the most advanced and trusted instant crypto lending provider on a global scale, servicing 40+ currencies across more than 200 jurisdictions.

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Nexo Token (NEXO) Smart Contract Security Audit Report

Are Your Funds Safe?


1. In scope

Сommit hash 3571169b3365adfc92c5bd743cc75b5184a2172a.

2. Findings

In total, 3 issues were reported including:

  • 1 low severity issues.

  • 1 note.

  • 1 owner privileges (the ability of an owner to manipulate contract, may be risky for investors).

No critical security issues were found.

2.1. Known vulnerabilities of ERC-20 token

Severity: low.


  • It is possible to double withdrawal attack. More details here.

2.2. Owner privileges

Severity: owner privileges.


Owner allows himself to call transferFrom function from investors, community and advisers address, so there is risk to investors, that owner will transfer this tokens to another address.

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2.3. Address is not correct

Severity: note.


Don’t forget to change addresses before deploy contract.

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3. Conclusion

The audited smart contract can be deployed. Only low severity issues were found during the audit.

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