---
id: CVE-2021-48018
aliases:
  - GHSA-7f92-rr6w-cq64
title: Storage corruption due to variables overwritten by re-entrancy locks
summary: Storage corruption due to variables overwritten by re-entrancy locks
severity: high
cvss: 7.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H'
vendor: vyper
product: vyper
ecosystem: pip
affected:
  - 'vyper >= 0.2.13, < 0.2.15'
patched:
  - vyper 0.2.15
published: '2021-08-05'
updated: '2026-10-24'
sourceUpdated: '2026-10-24T02:56:11.846071959Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-7f92-rr6w-cq64'
references:
  - url: 'https://github.com/vyperlang/vyper/security/advisories/GHSA-7f92-rr6w-cq64'
  - url: 'https://github.com/vyperlang/vyper/pull/2379'
  - url: 'https://github.com/vyperlang/vyper/pull/2391'
  - url: >-
      https://www.vulncheck.com/advisories/vyper-0.2.13-before-0.2.15-storage-corruption-via-nonreentrant-decorator
    label: >-
      VulnCheck Advisory: Vyper 0.2.13 before 0.2.15 Storage Corruption via
      @nonreentrant Decorator
tags:
  - osv
  - pip
  - cve.org
epss: 0.00391
epssPercentile: 0.33093
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-23T14:57:03.783104Z'
cvssSource: cna
cwe:
  - CWE-787
ingestedAt: '2026-10-21T01:37:08.048Z'
---

## Overview

### Background
When attempting to use the v0.2.14 release, @pandadefi discovered an issue using the `@nonreentrant` decorator.

### Impact
Reentrancy protection storage slots get allocated to the same slots as storage variables, leading to the corruption of storage variables when using the `@nonreentrant` decorator.

### Patches
This issue was fixed in v0.2.15 in #2391, #2379

### Workarounds
Don't use the `@nonreentrant` decorator in these versions.

## Affected packages

- `vyper >= 0.2.13, < 0.2.15`

## Remediation

Upgrade to a patched release:

- `vyper 0.2.15`