---
id: CVE-2026-113720
title: 'virtualenv: Seeded files retain permissions from an older cache'
summary: >-
  virtualenv is a tool for creating isolated virtual python environments. Prior
  to 21.14.9, the app-data copy seeder uses shutil.copy() to copy cached package
  files into later environments, causing cached source modes to override the
  curre…
severity: medium
cvss: 4.4
cvssVector: 'CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-732
vendor: pypa
product: virtualenv
affected:
  - virtualenv < 21.14.9
published: '2026-10-20'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T19:43:32.451Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-113720'
references:
  - url: 'https://github.com/pypa/virtualenv/security/advisories/GHSA-fc2g-4w5p-6whm'
    label: 'https://github.com/pypa/virtualenv/security/advisories/GHSA-fc2g-4w5p-6whm'
  - url: 'https://github.com/pypa/virtualenv/pull/3425'
    label: 'https://github.com/pypa/virtualenv/pull/3425'
  - url: >-
      https://github.com/pypa/virtualenv/commit/35f0b33562790176dd186d0a3c517af3acc7a0e1
    label: >-
      https://github.com/pypa/virtualenv/commit/35f0b33562790176dd186d0a3c517af3acc7a0e1
  - url: 'https://github.com/pypa/virtualenv/releases/tag/21.14.9'
    label: 'https://github.com/pypa/virtualenv/releases/tag/21.14.9'
tags:
  - cve.org
ingestedAt: '2026-10-20T20:18:14.532Z'
---

## Overview

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the app-data copy seeder uses shutil.copy() to copy cached package files into later environments, causing cached source modes to override the current run's umask. A cache populated under a permissive umask can therefore produce files writable by another local account in a later traversable environment, allowing package code such as pip/__init__.py to be modified and executed by the environment owner. The attacker cannot force the earlier umask, and a private destination parent prevents access. This issue is fixed in version 21.14.9.

## Affected

- `virtualenv < 21.14.9`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.