CVE-2018-13738 in PELOCoinToken
Summary
by MITRE
The mintToken function of a smart contract implementation for PELOCoinToken, 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 • 02/28/2020
The CVE-2018-13738 vulnerability represents a critical integer overflow flaw within the mintToken function of the PELOCoinToken smart contract deployed 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. The flaw specifically affects the token contract's ability to manage user balances through the mintToken function, which is designed to create new tokens and allocate them to specified addresses. When the mintToken function processes token creation requests, it does not properly validate or constrain the input parameters, allowing an attacker to manipulate the arithmetic operations that determine how many tokens are minted and assigned to target addresses.
The technical implementation of this vulnerability demonstrates a classic integer overflow condition where the mintToken function fails to perform bounds checking on the token amount being minted. In Ethereum smart contracts, this typically occurs when unsigned integer arithmetic operations exceed the maximum value that can be represented by the data type, causing the value to wrap around to zero or a negative value. The vulnerability is particularly dangerous because it grants the contract owner unprecedented control over user balances, enabling them to set any arbitrary value for any user account. This includes the ability to create infinite token balances for malicious addresses or manipulate existing balances to bypass tokenomics and governance mechanisms.
The operational impact of CVE-2018-13738 extends beyond simple balance manipulation to potentially compromise the entire token economy and user trust in the PELOCoinToken system. An attacker with owner privileges could exploit this vulnerability to create unlimited tokens, manipulate market dynamics, or gain unauthorized access to funds that should remain locked or restricted. The vulnerability directly violates fundamental security principles of blockchain tokenomics and could lead to significant financial losses for token holders and the broader ecosystem. Additionally, this flaw could be leveraged to undermine the integrity of any tokenomics model that relies on controlled token distribution and balance management, potentially affecting token value, liquidity, and the overall stability of the platform.
Mitigation strategies for CVE-2018-13738 should focus on immediate code remediation and comprehensive security auditing of the affected smart contract. The primary fix involves implementing proper bounds checking and overflow protection mechanisms within the mintToken function, typically through the use of require statements that validate input parameters before processing arithmetic operations. The contract should employ SafeMath libraries or similar arithmetic protection mechanisms to prevent integer overflows from occurring. Additionally, security audits should include comprehensive testing of all arithmetic operations, particularly those involving user-controlled inputs, to ensure that no similar vulnerabilities exist in other functions. Organizations should also consider implementing multi-signature ownership controls and regular security assessments to prevent unauthorized access to critical contract functions. This vulnerability aligns with CWE-190, Integer Overflow or Wraparound, and represents a significant risk under ATT&CK technique T1548.001, Abuse of Functionality, where attackers exploit legitimate system capabilities to achieve malicious outcomes. The remediation process must also include thorough testing of all contract functions to prevent similar issues in future deployments and ensure the integrity of the token ecosystem.