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TI-2026-78535 Aliases CVE-2026-113732GHSA-c947-3pg5-gm8q

Command injection in virtualenv fish activation script

Priority LOW 36CWE-116Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 5 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-78.

Summary

virtualenv before 21.14.2 generates an activate.fish script that quotes values with POSIX rules, which fish does not follow. A backslash before a quote in an attacker-influenced environment path, --prompt, or VIRTUALENV_PROMPT value ends the fish string and runs command substitution when the user sources the script (CWE-78).

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

Description from the CNA

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.2, FishActivator inherits ViaTemplateActivator.quote(), which uses POSIX shlex.quote() even though fish interprets backslashes and single quotes differently. An attacker-influenced environment path, --prompt, or VIRTUALENV_PROMPT value containing a backslash before a quote can therefore terminate the generated fish literal and execute command substitution when the user sources activate.fish. This issue is fixed in version 21.14.2.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00236 14th percentileScored 2026-11-07
Fix Partial virtualenv (pypa): 21.14.2virtualenv (PyPI): 21.14.2Red Hat: 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
pypavirtualenvbefore 21.14.221.14.2Patch availableCNA
—virtualenv (PyPI)before 21.14.221.14.2Patch availableGHSA-c947-3pg5-gm8q
  • virtualenv Vendorpypa Affected before 21.14.2 Fixed in 21.14.2 Patch available CNA
  • virtualenv (PyPI) Vendor— Affected before 21.14.2 Fixed in 21.14.2 Patch available GHSA-c947-3pg5-gm8q

Remediation

Upgrade virtualenv to version 21.14.2, which fixes the issue. Red Hat lists no fix planned for OpenShift Lightspeed and no fix available for Red Hat Ansible Automation Platform 2, Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Dev Spaces and Red Hat Satellite 6.

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

  • Fix · CNA virtualenv (pypa) Fixed in 21.14.2
  • Fix · GHSA-c947-3pg5-gm8q virtualenv (PyPI) Fixed in 21.14.2 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
OpenShift LightspeedAffectedNo fix planned: Will not fix
Red Hat Ansible Automation Platform 2AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift Dev SpacesAffectedNo fix yet
Red Hat Satellite 6AffectedNo fix yet
Not affected: 3 products
  • Red Hat Ansible Automation Platform 2
  • Red Hat OpenShift AI (RHOAI)
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-21 Threatist record created from CVE-2026-113732
  2. 2026-10-21 Affected versions changed · Red Hat
  3. 2026-10-21 CVSS score added · Red Hat
  4. 2026-10-21 Alias added: GHSA-c947-3pg5-gm8q
  5. 2026-10-21 Fix available: PyPI/[email protected] · GHSA-c947-3pg5-gm8q
  6. 2026-10-21 CVSS score added · GHSA-c947-3pg5-gm8q
  7. 2026-10-21 Weakness changed · GHSA-c947-3pg5-gm8q
  8. 2026-10-21 5 new references · GHSA-c947-3pg5-gm8q
  9. 2026-10-22 Priority changed: MEDIUM → LOW
  10. 2026-10-22 Affected versions changed · Red Hat
  11. 2026-10-27 CISA SSVC decision points changed
  12. 2026-11-02 Affected versions changed · Red Hat
  13. 2026-11-03 Affected versions changed · Red Hat
  14. 2026-11-07 Affected versions changed · Red Hat

References

Advisory 1

Other 4

  • 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
See all 36 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences