Is CVE-2026-113726 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-113726 being exploited in the wild.

How severe is CVE-2026-113726?

High severity, with a CVSS score of 7.8, published 20 October 2026.

Which products and versions are affected?

Pypa Virtualenv before 21.14.4; virtualenv (PyPI) <= 21.14.3, ECOSYSTEM:introduced=0,fixed=21.14.4.

Is there a fix for CVE-2026-113726?

Yes. virtualenv (PyPI): upgrade to 21.14.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-113726 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-113726?

Check whether you run Pypa Virtualenv or virtualenv (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-113726: pypa virtualenv command injection in bash activate script

Q: Is there a fix for CVE-2026-113726?

Yes. virtualenv (PyPI): upgrade to 21.14.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-113726 attacked?

It is attacked with local access, in a software library.

Q: Am I affected by CVE-2026-113726?

Check whether you run Pypa Virtualenv or virtualenv (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-113726 · Severity: high · CVSS 7.8 · Published 2026-10-20

virtualenv is a Python tool that creates isolated development environments. When used with zsh shell and PROMPT_SUBST enabled, an attacker can embed shell command syntax in a virtual environment's name or prompt configuration, causing arbitrary commands to execute whenever the shell prompt is drawn. This could allow code execution when a user activates a malicious virtual environment.

Technologies: Pypa Virtualenv, virtualenv (PyPI). Vendors: Pypa, PyPI.

Quick answers

Is CVE-2026-113726 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-113726 being exploited in the wild.
How severe is CVE-2026-113726?: High severity, with a CVSS score of 7.8, published 20 October 2026.
Which products and versions are affected?: Pypa Virtualenv before 21.14.4; virtualenv (PyPI) <= 21.14.3, ECOSYSTEM:introduced=0,fixed=21.14.4.
Is there a fix for CVE-2026-113726?: Yes. virtualenv (PyPI): upgrade to 21.14.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-113726 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-113726?: Check whether you run Pypa Virtualenv or virtualenv (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

virtualenv (PyPI): upgrade to 21.14.4 or later
```
pip install "virtualenv>=21.14.4"
```

Technical details

The bash activate script sourced by zsh fails to properly escape shell metacharacters (command substitution syntax like $(...) and backticks) in the environment name before assigning it to the PS1 prompt variable. With zsh's PROMPT_SUBST option enabled, PS1 is re-evaluated at each prompt draw, causing embedded expansions to execute. The vulnerability affects versions prior to 21.14.4; versions 21.13.0–21.14.3 only escaped under bash (when BASH_VERSION is set), leaving zsh vulnerable. Plain bash and zsh without PROMPT_SUBST are not affected.

Affected products

pypa virtualenv before 21.14.4

Identifiers

CVE-2026-113726
GHSA-5vjq-rrrf-7h2q

Timeline

2026-10-20: disclosed

References

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