vyperlang Vyper up to 0.5.0b1 Optimizer comparison

Summaryinfo

A vulnerability was found in vyperlang Vyper up to 0.5.0b1. It has been rated as problematic. This issue affects some unknown processing of the component Optimizer. This manipulation causes comparison. This vulnerability is registered as CVE-2026-114117. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as problematic was found in vyperlang Vyper up to 0.5.0b1. Affected by this vulnerability is an unknown function of the component Optimizer. The manipulation with an unknown input leads to a comparison vulnerability. The CWE definition for the vulnerability is CWE-697. The product compares two entities in a security-relevant context, but the comparison is incorrect, which may lead to resultant weaknesses. As an impact it is known to affect integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-114117 since 10/20/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/21/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• vyperlang

Name

• Vyper

Version

• 0.5.0b1

Website

• Product: https://github.com/vyperlang/vyper/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion