CVE-2018-13570 in kkTestCoin1
Summary
by MITRE
The mint function of a smart contract implementation for kkTestCoin1 (KTC1), 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 • 02/27/2020
The vulnerability identified as CVE-2018-13570 resides within the mint function of kkTestCoin1 (KTC1) smart contract implementation on the Ethereum blockchain. This represents a critical security flaw that directly impacts the contract's ability to maintain accurate token balances and overall system integrity. The vulnerability stems from improper input validation and arithmetic handling within the mint function, creating an exploitable condition that allows malicious actors to manipulate token distributions.
The technical flaw manifests as an integer overflow condition that occurs when the mint function processes token creation requests. When the contract attempts to increment user balances through the mint operation, it fails to properly validate or constrain the input values, allowing an attacker to craft malicious transactions that exploit the overflow behavior. This specific implementation flaw enables the contract owner to manipulate the balance of any user account to arbitrary values, effectively bypassing normal token distribution controls and potentially enabling unlimited token generation. The vulnerability directly maps to CWE-190, which describes integer overflow conditions, and CWE-682, which covers incorrect arithmetic operations that can lead to unexpected behavior in software systems.
The operational impact of this vulnerability extends beyond simple financial manipulation to potentially compromise the entire token economy and user trust in the system. An attacker with access to the contract owner privileges can arbitrarily inflate user balances, effectively creating an unlimited money supply or redistributing tokens in unauthorized ways. This could result in significant financial losses for legitimate users who may see their token values diluted or redistributed without their consent. The vulnerability also undermines the fundamental principles of blockchain tokenomics and smart contract security, as it allows for unauthorized control over token distribution mechanisms. From an attack perspective, this vulnerability aligns with ATT&CK technique T1548.001, which covers abuse of privileges through code injection or manipulation of system-level functions, and T1499.004, which involves data manipulation through unauthorized access to system resources.
Mitigation strategies for this vulnerability require immediate implementation of proper input validation and arithmetic boundary checking within the mint function. The smart contract should incorporate explicit overflow checks using modern solidity practices such as require statements with appropriate bounds validation before any arithmetic operations. Additionally, the contract owner should implement proper access controls and audit mechanisms to monitor unauthorized balance modifications. The fix should also include comprehensive testing procedures including fuzz testing and formal verification to ensure that similar vulnerabilities do not exist in other arithmetic operations within the contract. Regular security audits and third-party code reviews should become standard practice to identify and remediate such critical flaws before they can be exploited in production environments.