CVE-2018-13764 in BiquToken
Summary
by MITRE
The mintToken function of a smart contract implementation for BiquToken, an Ethereum token, has an integer overflow that allows the owner of the contract to set the balance of an arbitrary user to any value.
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Analysis
by VulDB Data Team • 03/03/2020
The vulnerability identified as CVE-2018-13764 represents a critical integer overflow flaw within the mintToken function of the BiquToken smart contract implementation on the Ethereum blockchain. This vulnerability stems from improper input validation and arithmetic operations that fail to account for the maximum limits of integer data types, creating a scenario where malicious actors can manipulate token balances through controlled overflow conditions. The flaw specifically affects the contract's ability to safely increment token balances during the minting process, allowing for arbitrary value manipulation that fundamentally compromises the integrity of the token economy.
The technical execution of this vulnerability occurs when the mintToken function processes user inputs without adequate overflow checking mechanisms. When an attacker provides carefully crafted values that cause integer overflow during balance calculations, the system fails to properly validate the resulting arithmetic operations. This allows the contract owner to manipulate the balance of any user account to an arbitrary value, effectively bypassing normal token distribution and transfer restrictions. The vulnerability is classified under CWE-190, which specifically addresses integer overflow and underflow conditions, and aligns with ATT&CK technique T1059.001 for execution through smart contract manipulation. The flaw exists due to the absence of proper boundary checks and the lack of overflow detection mechanisms in the contract's arithmetic operations.
The operational impact of this vulnerability extends beyond simple balance manipulation to potentially compromise the entire token ecosystem and user trust in the platform. An attacker with access to the contract owner privileges can arbitrarily inflate or deflate user balances, leading to potential financial losses for token holders and undermining the fundamental principles of blockchain-based asset management. The vulnerability enables scenarios where attackers can create unlimited tokens, manipulate market dynamics, or even execute theft operations by setting balances to extremely high values that exceed normal operational parameters. This flaw directly impacts the security model of the Ethereum token and can lead to significant financial losses, regulatory scrutiny, and reputational damage for the project.
Mitigation strategies for CVE-2018-13764 require immediate implementation of comprehensive input validation and overflow protection mechanisms within the smart contract code. The most effective approach involves adding explicit overflow checks using modern solidity practices such as require statements with boundary conditions, or employing libraries like OpenZeppelin's SafeMath to prevent arithmetic overflows. Contract owners should implement comprehensive testing procedures including formal verification and fuzzing to identify similar vulnerabilities before deployment. Additionally, the implementation of access control measures and multi-signature requirements for critical functions like mintToken can reduce the attack surface. Organizations should also consider conducting regular security audits and implementing continuous monitoring systems to detect anomalous behavior in token contracts. The remediation process must include thorough code review procedures that specifically address integer arithmetic operations and ensure compliance with established security standards and best practices for blockchain smart contract development.