CVE-2020-37289 (GCVE-0-2020-37289)
Vulnerability from cvelistv5
Published
2026-10-21 00:36
Modified
2026-10-28 15:45
Severity ?
6.3 (Medium) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
3.7 (Low) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-20 - Improper Input Validation
Summary
Vyper before 0.3.1 lacks a uint8 type, allowing interface return values declared as uint8, such as ERC20.decimals(), to be stored in uint256 variables without bounds checking. Malicious contracts can return values greater than 255 to manipulate or bypass contract logic that relies on these values.
References
Impacted products
Vendor Product Version
vyperlang vyper Version: 0
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