CVE-2023-46247 : Vulnerability Insights and Analysis
Learn about CVE-2023-46247 impacting Vyper contracts with large arrays. Discover the vulnerability details, impact, affected versions, and mitigation steps.
Vyper has incorrect storage layout for contracts containing large arrays.
Understanding CVE-2023-46247
Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Contracts containing large arrays might underallocate the number of slots they need by 1.
What is CVE-2023-46247?
Prior to v0.3.8, the calculation to determine how many slots a storage variable needed used
math.ceil(type_.size_in_bytes / 32)The Impact of CVE-2023-46247
This vulnerability can result in an incorrect storage layout for contracts containing large arrays, potentially impacting the integrity of the data stored within these contracts. Attackers could exploit this vulnerability to manipulate the storage layout and compromise the data integrity.
Technical Details of CVE-2023-46247
The vulnerability is classified under CWE-193 (Off-by-one Error) and CWE-682 (Incorrect Calculation). The CVSS V3.1 base score is 7.5, indicating a high severity vulnerability.
Vulnerability Description
The calculation method for determining the number of slots needed for storage variables in Vyper contracts can lead to incorrect estimations and potential rounding errors, affecting the storage layout.
Affected Systems and Versions
Vyper versions prior to v0.3.8 are affected by this vulnerability. Specifically, versions below 0.3.8 may experience the incorrect storage layout for contracts containing large arrays.
Exploitation Mechanism
Attackers can potentially exploit this vulnerability by manipulating the storage layout of contracts with large arrays, leading to data integrity issues and potential security breaches.
Mitigation and Prevention
It is crucial to take immediate steps to address and mitigate the impact of CVE-2023-46247.
Immediate Steps to Take
Developers and users are advised to upgrade to Vyper version 0.3.8 or later to patch the vulnerability and ensure correct storage layout calculations for contracts with large arrays.
Long-Term Security Practices
Implement secure coding practices, conduct regular security audits, and stay informed about updates and patches released by Vyper to prevent future vulnerabilities.
Patching and Updates
Regularly update Vyper to the latest version to benefit from security patches, bug fixes, and enhancements that address known vulnerabilities and improve overall system security.