CVE-2026-114663

Description

Vyper 0.4.0b1 through 0.5.0b1 miscompiles unfoldable constants and omitted default arguments from imported modules, because parse_Name resolves their names in the using function's scope rather than at declaration. When a contract's parameter, local, or loop variable shares such a name, attacker-influenced input can replace the intended value, including out-of-range values for narrow types such as uint8, corrupting validation or accounting logic.

References

• https://github.com/vyperlang/vyper/security/advisories/GHSA-2489-32vh-8rrc
• https://www.vulncheck.com/advisories/vyper-0.4-0b1-through-0.5-0b1-name-shadowing-of-imported-constants-and-default-arguments