CVE-2018-13512 in SmartHomeCoin
Summary
by MITRE
The mintToken function of a smart contract implementation for SmartHomeCoin, 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-2018-13512 represents a critical integer overflow flaw within the mintToken function of SmartHomeCoin's Ethereum smart contract implementation. This vulnerability resides in the contract's token creation mechanism where the owner can manipulate user balances through improper integer handling. The flaw allows for arbitrary balance manipulation that fundamentally compromises the contract's integrity and token economics. The vulnerability directly maps to CWE-190, which specifically addresses integer overflow conditions where an attacker can cause a signed integer to exceed its maximum representable value, leading to unexpected behavior in the system. From an operational perspective, this vulnerability creates a severe risk for token holders as the contract owner can arbitrarily inflate or deflate user balances, potentially leading to total loss of funds or manipulation of token distributions.
The technical exploitation of this vulnerability occurs when the mintToken function processes token creation requests without proper overflow checks on integer values. In Ethereum smart contracts, this typically manifests when arithmetic operations are performed on uint256 variables without overflow protection mechanisms. The attacker can leverage this flaw to set any user's balance to an arbitrary value, effectively allowing for unlimited token generation or balance manipulation. The vulnerability's impact extends beyond simple balance manipulation as it undermines the fundamental trust model of the token system, enabling the contract owner to potentially drain all token reserves or create artificial scarcity. This flaw aligns with ATT&CK technique T1059.006, which covers smart contract manipulation and code injection attacks that exploit implementation weaknesses in blockchain systems.
The operational consequences of CVE-2018-13512 are severe and multifaceted, affecting both the token economy and user trust within the SmartHomeCoin ecosystem. Users may experience sudden balance changes without any legitimate reason, while the contract owner gains unprecedented control over the token distribution mechanism. This vulnerability essentially provides the owner with a backdoor to manipulate the entire token supply, potentially leading to market manipulation or complete loss of user funds. The financial impact could be catastrophic, as users might lose confidence in the token and withdraw their investments, causing significant market disruption. Additionally, the vulnerability creates potential regulatory concerns as it may constitute a form of unauthorized asset manipulation or fraud within the decentralized finance ecosystem.
Mitigation strategies for this vulnerability must focus on implementing proper integer overflow protection mechanisms within the smart contract code. The recommended approach involves adding explicit overflow checks using modern Solidity versions that include built-in overflow protection or implementing require statements to validate input parameters before processing token creation requests. The contract should enforce proper bounds checking on all arithmetic operations and utilize SafeMath libraries or similar protection mechanisms to prevent integer overflows. From a security posture perspective, regular code audits and formal verification of smart contracts should be implemented to identify similar vulnerabilities before deployment. The vulnerability also highlights the importance of conducting thorough security assessments during the smart contract development lifecycle, as outlined in industry best practices for blockchain security. Additionally, implementing multi-signature ownership controls and time locks for critical functions can provide additional layers of protection against unauthorized manipulation of token balances and contract parameters.