By Null Ventures MCP platform
Menu

vulnerability / NVI-00011891 / Revision 1

virtualenv activate runs commands from the environment name in zsh with PROMPT_SUBST

GitHub lists this reviewed advisory for virtualenv. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.

source listedactiveGHSA-5vjq-rrrf-7h2qCVE-2026-113726

This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.

01 / Meaning

Why it matters

Published affected context helps an owner decide what evidence to gather. This report has not examined your application.

CVSS

7.8 high

GitHub source severity; exploitability and local consequence require separate evidence.

As of · GitHub Advisory Database

02 / Applicability

The affected context

Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.

virtualenv

source listed
  • <= 21.14.3

### Impact zsh users activate an environment with the bash `activate` script, which puts the environment name into `PS1`. Since 21.13.0 the script escapes backslashes, dollar signs and backticks in that name, but only when `BASH_VERSION` is set, so zsh gets the raw value. With the `PROMPT_SUBST` option set, zsh runs parameter expansion, command substitution and arithmetic expansion on `PS1` each time it draws the prompt. A name that contains `$(...)`, backticks or `${...}` then runs as commands in the user's shell, once per prompt. The name comes from the environment directory, or from `--prompt` or `VIRTUALENV_PROMPT`. After you create an environment with: ```console $ virtualenv 'x$(touch PWNED)y' ``` `source 'x$(touch PWNED)y/bin/activate'` in a zsh session with `PROMPT_SUBST` set creates `PWNED`, and the prompt shows `(xy)`. Passing that value as `--prompt` to an environment with a plain name has the same effect. Without `PROMPT_SUBST`, zsh shows the name as text and runs nothing. bash runs nothing either. A plain zsh starts with `PROMPT_SUBST` off. oh-my-zsh users have it on: oh-my-zsh loads [`lib/theme-and-appearance.zsh`](https://github.com/ohmyzsh/ohmyzsh/blob/4d4cfc28

GitHub Advisory Database

03 / Response

What to do next

  1. investigate

    Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database

A fixed release is not deployment evidence.

Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.

04 / Limits

What this report cannot establish

  • Customer inventory, deployment, reachability and exploitation have not been inspected.
Read the collection and interpretation limits ↗

05 / Provenance

Sources you can inspect

Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.

  1. GHSA-5vjq-rrrf-7h2q ↗

    GitHub Advisory Database · vendor advisory

    Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.

Public revision history

Only published revisions appear here. Routine fetches do not create a material-change event.

  1. Revision 1 ·

    First indexed by Null; source disclosure date is shown separately.

Read the public revision data ↗

The next step is private

Bring the question into your environment.

The connected workflow is a development preview for inventory, contextual matching, owner decisions and evidence-based verification. No system-specific result is generated by this page.

See the synthetic workflow preview ↗