Link following in virtualenv builtin creator writes outside target
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · Low
- Fix status
- Partial Red Hat: 6 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
virtualenv before 21.14.9 is affected. Its builtin creator accepts an existing symlink to a directory for executable, library and package directories, so writes follow it outside the requested destination (CWE-59). A local user who prepares the directory tree beforehand can redirect interpreter creation, seed installation and activation script writes when the invoking user can reach the target.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the builtin creator calls ensure_dir() for executable, library, and package directories, and ensure_dir() accepts an existing symlink to a directory because exists() follows it. Interpreter creation, seed installation, and activation generation then write through the linked parent outside the requested destination when another local account prepared the tree and the invoking user can access the target. The --clear option removes the planted tree first, while ordinary creation reaches it; arbitrary attacker-selected output bytes are not established. This issue is fixed in version 21.14.9.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| pypa | virtualenv | before 21.14.9 | 21.14.9 | Patch available | CNA |
| — | virtualenv (PyPI) | before 21.14.9 | 21.14.9 | Patch available | GHSA-cw65-gx24-rc82 |
- virtualenv Vendorpypa Affected before 21.14.9 Fixed in 21.14.9 Patch available CNA
- virtualenv (PyPI) Vendor— Affected before 21.14.9 Fixed in 21.14.9 Patch available GHSA-cw65-gx24-rc82
Remediation
Upgrade to virtualenv 21.14.9 on PyPI, which fixes the flaw. Red Hat lists OpenShift Lightspeed, Red Hat Ansible Automation Platform 2, Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Container Platform 4, Red Hat OpenShift Dev Spaces and Red Hat Satellite 6 as affected, with no plan available for a fix.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA virtualenv (pypa) Fixed in 21.14.9
- Fix · GHSA-cw65-gx24-rc82 virtualenv (PyPI) Fixed in 21.14.9 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| OpenShift Lightspeed | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform 2 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Dev Spaces | Affected | No fix yet: Fix deferred |
| Red Hat Satellite 6 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-20 Threatist record created from CVE-2026-113716
- 2026-10-21 Affected versions changed · Red Hat
- 2026-10-21 CVSS score added · Red Hat
- 2026-10-21 CISA SSVC decision points changed
- 2026-10-21 Alias added: GHSA-cw65-gx24-rc82
- 2026-10-21 Fix available: PyPI/[email protected] · GHSA-cw65-gx24-rc82
- 2026-10-21 CVSS score added · GHSA-cw65-gx24-rc82
- 2026-10-21 Weakness changed · GHSA-cw65-gx24-rc82
- 2026-10-21 6 new references · GHSA-cw65-gx24-rc82
References
More pypa vulnerabilities
- TI-2025-29803 setuptools has a path traversal vulnerability in PackageIndex.download that leads to Arbitrary File Write CVSS 4.0HIGH 7.7
- TI-2024-05888 Remote Code Execution in pypa/setuptools CVSS 3.0HIGH 8.8
- TI-2026-78525 Shell command injection in virtualenv generated POSIX launchers CVSS 3.1HIGH 7.8
- TI-2026-78526 Command injection in virtualenv bash activation prompt CVSS 4.0HIGH 7.1
- TI-2026-78521 Code injection in virtualenv Xonsh activation script CVSS 4.0HIGH 7.1
- TI-2026-19377 wheel Allows Arbitrary File Permission Modification via Path Traversal CVSS 3.1HIGH 7.1
Sources
- CVE-2026-113716 · CVE Program
- CVE-2026-113716 · NVD
- FIRST EPSS
- GHSA-cw65-gx24-rc82 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-113716 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences