---
id: "CVE-2026-114118"
kind: "vulnerability"
aliases: ["CVE-2026-114118"]
title: "Vyper: blueprint deploy lets bad offset create empty contracts, trapping funds"
severity: "medium"
cvss: 6.3
epss: 0.00201
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["ethereum", "factory-contracts", "package", "smart-contracts", "vyper"]
not_affected_if: ["no-create-from-blueprint", "offset-not-user-controlled", "other-vyper-version"]
published_at: "2026-10-21T01:17:38+00:00"
first_seen_at: "2026-10-23T21:57:28+00:00"
updated_at: "2026-10-25T04:01:21+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-114118", "first_seen_at": "2026-10-23T21:57:28+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-114118", "first_seen_at": "2026-10-24T13:15:54+00:00"}]
---

# Vyper: blueprint deploy lets bad offset create empty contracts, trapping funds

Vyper 0.3.4 through 0.5.0b1 computes the remaining blueprint size in create_from_blueprint with unchecked uint256 subtraction, so a large code_offset wraps to a small positive value. An attacker who controls code_offset can make a factory deploy contracts with no runtime code, which can trap ETH and tokens sent to them.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Vyper version in the project, for example with `vyper --version` or the pinned version in the lockfile or build config, and see whether it falls in 0.3.4 through 0.5.0b1.
- Search the contracts for `create_from_blueprint` and check whether `code_offset` can come from user input or an untrusted caller.

## Fix

- Move Vyper to a version after 0.5.0b1; the sources do not name the fixed release, so check the Vyper release notes.
- Until upgraded, validate or restrict `code_offset` in factory contracts so it is always below the blueprint code size.

## Timeline

- 2026-10-23T21:57:28+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-114118
- 2026-10-24T13:15:54+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-114118

## From the sources

Vyper 0.3.4 through 0.5.0b1 computes the remaining blueprint size in create_from_blueprint by uint256 subtraction without first checking that code_offset is below the blueprint's code size, so a huge offset wraps to a small positive value. An attacker controlling code_offset can make a factory deploy contracts with no runtime code, potentially trapping ETH and tokens.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_