CVE-2020-37289
Vyper before 0.3.1 Improper Input Validation of uint8 Interface Return Values
- State
- Published
- Severity
- 6.3 Medium
- Published
- Oct 21, 2026
- Updated
- Oct 28, 2026
- Reserved
- Oct 20, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 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 | VulnCheck |
| 3.1 | 3.7 Low | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N | VulnCheck |
Weaknesses
- CWE-20 Improper Input Validation
Affected Products
| Product | Versions |
|---|---|
vypervyperlang |
|
References
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