CVE-2018-13630 in DoccoinPreICO
Summary
by MITRE
The mintToken function of a smart contract implementation for DoccoinPreICO, 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 vulnerability identified in CVE-2018-13630 represents a critical integer overflow flaw within the mintToken function of the DoccoinPreICO smart contract implementation running on the Ethereum blockchain. This vulnerability stems from improper input validation and arithmetic handling within the contract's code, specifically affecting how the contract manages token minting operations. The flaw allows an attacker with ownership privileges to manipulate the balance of any user account within the token system, creating a fundamental breach in the contract's integrity and token distribution mechanisms.
The technical implementation of this vulnerability occurs when the mintToken function processes token creation requests without adequate overflow protection mechanisms. In Ethereum smart contracts, integer overflow vulnerabilities typically arise when arithmetic operations exceed the maximum value that can be stored in a given data type, causing the value to wrap around to zero or negative values. The DoccoinPreICO contract's mintToken function fails to validate input parameters properly, enabling an attacker to craft malicious inputs that trigger the overflow condition. This condition allows the contract owner to manipulate the balance of arbitrary user accounts by setting values that exceed the maximum integer limits, effectively bypassing normal token distribution controls.
The operational impact of this vulnerability extends far beyond simple financial manipulation, as it fundamentally compromises the trust model that underpins the entire token ecosystem. An attacker with ownership access can arbitrarily inflate or deflate user balances, potentially creating artificial scarcity or abundance of tokens within the system. This capability undermines the core principles of blockchain-based tokenomics and can lead to significant financial losses for legitimate token holders. The vulnerability also creates potential for denial-of-service attacks where an attacker could manipulate balances to prevent users from accessing their tokens, or conversely, flood the system with artificially inflated balances. From a security perspective, this flaw represents a privilege escalation vulnerability that allows a single compromised account to affect the entire token distribution system, making it particularly dangerous in pre-ico environments where trust in the development team is paramount.
Mitigation strategies for CVE-2018-13630 require immediate code remediation to implement proper overflow protection mechanisms within the mintToken function. The recommended approach involves using safe arithmetic libraries or implementing explicit overflow checks before any arithmetic operations occur, ensuring that all integer calculations remain within valid bounds. Additionally, the contract should enforce strict input validation on all parameters passed to the mintToken function, including minimum and maximum value constraints that prevent malicious manipulation. From a broader security standpoint, this vulnerability highlights the importance of implementing comprehensive testing procedures including formal verification and automated security scanning tools that can detect such arithmetic overflow conditions. The fix should also consider implementing access control measures that limit the privileges of the contract owner and introduce multi-signature requirements for critical operations, reducing the risk of unauthorized balance manipulation. This vulnerability aligns with CWE-190, Integer Overflow or Wraparound, and represents a critical threat vector that can be exploited through the ATT&CK technique of Privilege Escalation by manipulating contract state through controlled input parameters.
The broader implications of this vulnerability extend to the Ethereum smart contract ecosystem, where similar integer overflow flaws have been documented across numerous token implementations. Security researchers have identified patterns in how developers approach arithmetic operations in smart contracts, with many failing to implement proper overflow protection mechanisms. This particular vulnerability demonstrates the critical need for standardized security practices and code review processes within blockchain development environments. Organizations deploying smart contracts should implement comprehensive security testing procedures that include vulnerability scanning, code analysis, and peer review processes to identify and remediate such critical flaws before deployment. The incident also underscores the importance of maintaining up-to-date security practices and understanding the specific attack vectors that are unique to blockchain-based systems, as traditional software security approaches may not adequately address the unique challenges presented by smart contract environments.