CVE-2026-114117

Vyper 0.3.8 through 0.5.0b1 contains an optimizer miscompilation in which (msg.value | K) or (len(msg.data) | K), where K is any nonzero integer literal, is compiled to the constant 1 when used as a ternary expression branch under -O gas (the default) or -O codesize. Affected contracts use the wrong value in storage writes, arithmetic, indexes, return values, or events without warning or revert, which can record deposits incorrectly and lock funds.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/vyperlang/vyper/security/advisories/GHSA-6j9c-gvcw-74fj
https://www.vulncheck.com/advisories/vyper-0.3.8-through-0.5-0b1-optimizer-miscompilation-of-msg-value-k-in-ternary-branches
https://github.com/vyperlang/vyper/security/advisories/GHSA-6j9c-gvcw-74fj

Configurations

No configuration.

History

21 Oct 2026, 21:17

Type	Values Removed	Values Added
References	~~() https://github.com/vyperlang/vyper/security/advisories/GHSA-6j9c-gvcw-74fj -~~	() https://github.com/vyperlang/vyper/security/advisories/GHSA-6j9c-gvcw-74fj -

21 Oct 2026, 01:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-21 01:17

Updated : 2026-10-22 17:00

NVD link : CVE-2026-114117

Mitre link : CVE-2026-114117

CVE.ORG link : CVE-2026-114117

JSON object : View

Products Affected

No product.

CWE

CWE-682

Incorrect Calculation

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