CVE-2020-37289

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.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/vyperlang/vyper/security/advisories/GHSA-mr6r-mvw4-736g
https://www.vulncheck.com/advisories/vyper-before-0.3.1-improper-input-validation-of-uint8-interface-return-values

Configurations

No configuration.

History

21 Oct 2026, 01:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-21 01:17

Updated : 2026-10-28 16:16

NVD link : CVE-2020-37289

Mitre link : CVE-2020-37289

CVE.ORG link : CVE-2020-37289

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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