CVE-2018-13173 in EliteShipperToken
Summary
by MITRE
The mintToken function of a smart contract implementation for EliteShipperToken (ESHIP), 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 • 02/25/2020
The CVE-2018-13173 vulnerability resides within the EliteShipperToken (ESHIP) smart contract implementation on the Ethereum blockchain, representing a critical integer overflow flaw that fundamentally compromises the contract's integrity and security model. This vulnerability specifically affects the mintToken function, which serves as a mechanism for creating new tokens and allocating them to user accounts. The flaw stems from improper input validation and arithmetic handling within the smart contract's code, creating a scenario where the owner can manipulate token balances without proper authorization or oversight. The vulnerability operates at the core level of the token's accounting system, where the mathematical operations used to calculate and update user balances fail to account for potential overflow conditions that could result in unexpected and potentially malicious value assignments.
The technical execution of this vulnerability leverages the fundamental properties of integer arithmetic in smart contract environments, where fixed-size integer variables can exceed their maximum representable values when performing mathematical operations. When the mintToken function processes token creation requests, it fails to implement proper overflow checks that would normally be enforced by modern programming languages or blockchain frameworks. This allows the contract owner to manipulate the internal balance tracking mechanisms by providing carefully crafted parameters that cause integer overflow conditions to produce desired outcomes. The vulnerability maps directly to CWE-190, which specifically addresses integer overflow conditions, and represents a classic example of improper input validation in smart contract development. The attacker can exploit this by calculating specific values that when processed through the vulnerable arithmetic operations produce overflow results that effectively set any user's balance to an arbitrary value, including potentially unlimited amounts.
The operational impact of CVE-2018-13173 extends far beyond simple financial manipulation, as it fundamentally undermines the trust model that underpins blockchain-based token systems and creates cascading security risks throughout the ecosystem. The vulnerability enables the contract owner to potentially drain token reserves, create artificial scarcity, or manipulate token distributions in ways that could destabilize market dynamics and investor confidence. This type of flaw represents a severe breach of the principle of least privilege, as it grants the contract owner unprecedented control over user accounts that should remain protected from unauthorized modifications. The implications for the broader Ethereum ecosystem are significant, as similar vulnerabilities in other token contracts could create widespread financial losses and erode trust in smart contract implementations. The vulnerability also aligns with ATT&CK technique T1548.001, which covers privilege escalation through code injection, as the owner effectively escalates their privileges to manipulate user balances beyond normal operational parameters.
Mitigation strategies for CVE-2018-13173 require immediate implementation of robust input validation and overflow protection mechanisms within the smart contract code, including the adoption of modern Solidity practices such as using require statements for boundary checks and implementing proper overflow protection through libraries like OpenZeppelin's SafeMath. The contract should be audited for similar vulnerabilities in other arithmetic operations, particularly functions that handle token transfers, minting, and burning. Regular security audits and formal verification processes should be implemented to identify and remediate such issues before deployment. Additionally, contract owners should consider implementing multi-signature controls and time locks for critical functions to prevent unauthorized exploitation. The vulnerability also underscores the importance of following established security frameworks and best practices for smart contract development, including comprehensive testing of edge cases and mathematical operations to ensure that all possible input values are properly handled within the constraints of the underlying blockchain's computational model.