CVE-2018-13654 in ESTSToken
Summary
by MITRE
The mintToken function of a smart contract implementation for ESTSToken, 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.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 02/28/2020
The vulnerability identified in CVE-2018-13654 represents a critical integer overflow flaw within the mintToken function of the ESTSToken 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 handle large numeric values during token minting operations, allowing unauthorized manipulation of user account balances.
The technical exploitation of this vulnerability occurs when the mintToken function processes token creation requests without proper overflow checks on the balance calculations. When the contract attempts to increment a user's token balance beyond the maximum value that can be represented by the underlying integer type, the overflow condition causes the value to wrap around to a much smaller number, effectively allowing the contract owner to manipulate account balances to arbitrary values. This behavior directly violates the fundamental principles of blockchain tokenomics where each user's balance should be accurately tracked and immutable.
From an operational impact perspective, this vulnerability creates severe security implications for any system relying on the ESTSToken contract for asset management and transaction processing. The contract owner can artificially inflate or deflate user balances, potentially leading to unauthorized token distribution, manipulation of tokenomics, and complete compromise of the token's integrity. The vulnerability affects the core functionality of the token system, undermining trust in the blockchain-based asset and potentially enabling financial losses for users who hold tokens in affected contracts. This flaw directly relates to CWE-190, Integer Overflow or Wraparound, which is classified as a high-severity vulnerability in software security practices.
The exploitation of this vulnerability aligns with several tactics outlined in the MITRE ATT&CK framework for blockchain-based attacks, particularly focusing on privilege escalation and data manipulation techniques. Attackers can leverage this flaw to gain unauthorized control over token distributions and user balances, effectively bypassing normal access controls and authorization mechanisms. The vulnerability also represents a significant concern for compliance and regulatory frameworks that require accurate accounting and transparent transaction records in financial systems. Organizations utilizing smart contracts must implement proper input validation and boundary checking mechanisms to prevent similar integer overflow conditions from occurring in their blockchain implementations.
Mitigation strategies for this vulnerability include implementing comprehensive input validation, utilizing safe arithmetic libraries that handle overflow conditions gracefully, and conducting thorough code audits for all smart contract implementations. The fix requires modifying the mintToken function to include proper bounds checking and overflow detection mechanisms, ensuring that balance calculations cannot exceed the maximum representable integer values. Additionally, implementing proper access controls and regular security assessments can help prevent similar vulnerabilities from being introduced in future smart contract deployments, maintaining the integrity and security of blockchain-based token systems.