CVE-2026-113721 virtualenv: Generated files can follow existing destination links
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-113721?
CVE-2026-113721 is a medium-severity vulnerability in pypa virtualenv, published on 20 Oct 2026.
Official description
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, ViaTemplateActivator._generate() removes an existing output only when Path.exists() is true, allowing a dangling symlink to survive and redirect generated activation content, while PyEnvCfg.write() opens pyvenv.cfg without first replacing an existing symbolic or hard link. Another local account that prepares final entries inside the destination can therefore cause environment creation to create or overwrite files outside the requested tree with constrained virtualenv-generated content and the invoking user's permissions. The destination parent must remain controlled by the environment owner during creation; concurrent parent-directory replacement is a separate concern. This issue is fixed in version 21.14.9.
Weakness: CWE-59
Which versions are affected by CVE-2026-113721?
3 open source packages ship an affected version, including virtualenv.
| Package | Affected | Fixed in |
|---|---|---|
virtualenv Bitnami | All versions | 21.14.9 |
virtualenv PyPI | All versions | 21.14.9 |
virtualenv PyPI | All versions | 21.14.9 |
How do I fix CVE-2026-113721?
Upgrade virtualenv to 21.14.9 or later.
Is CVE-2026-113721 being exploited?
There is no known exploitation of CVE-2026-113721 in the wild and no public exploit code.
Sources
Also known as AZL-110124, BIT-virtualenv-2026-113721, DEBIAN-CVE-2026-113721, ECHO-06e8-531f-8b53, GHSA-558c-9hv2-4prj, MINI-8v88-356f-hmv8 and 1 more.