medium4.4
CVE-2026-113720
virtualenv is a tool for creating isolated virtual python environments.
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | virtualenv | < 21.14.9 | 21.14.9 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-fc2g-4w5p-6whm
- https://github.com/pypa/virtualenv/security/advisories/GHSA-fc2g-4w5p-6whm
- https://nvd.nist.gov/vuln/detail/CVE-2026-113720
- https://github.com/pypa/virtualenv/pull/3425
- https://github.com/pypa/virtualenv/commit/35f0b33562790176dd186d0a3c517af3acc7a0e1
- https://github.com/pypa/virtualenv/releases/tag/21.14.9