CVE-2026-113726virtualenv activate runs commands from the environment name in zsh with PROMPT_SUBST
Updated under an hour ago ()
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It affects pypa virtualenv. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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virtualenv is a tool for creating isolated virtual python environments. Prior to 21.13.0, the bash activate script that zsh also sources leaves the environment name unescaped; from 21.13.0 until 21.14.4, it escapes backslashes, dollar signs, and backticks only when BASH_VERSION is set, so zsh receives the raw value. The script assigns that value to PS1. In zsh with PROMPT_SUBST, an attacker-influenced environment directory, --prompt, or VIRTUALENV_PROMPT value containing command, parameter, or arithmetic expansion syntax can therefore execute commands in the user's shell each time the prompt is drawn. A percent sign is separately interpreted as a zsh prompt escape but does not by itself execute commands. Plain zsh with PROMPT_SUBST disabled and bash are not affected by this mechanism. This issue is fixed in version 21.14.4.
- CVSS
- 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-78, CWE-116
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- GitHub_M
- NVD analysis
- Received
- Record last updated
- Oct 20, 2026
- First seen by InfoSec Signals
- Oct 20, 2026
Affected products
pypa virtualenv pypa:virtualenv (from the name) | before 21.14.4 | CNA record |
References
- https://github.com/pypa/virtualenv/security/advisories/GHSA-5vjq-rrrf-7h2qx-refsource-confirm
- https://github.com/pypa/virtualenv/commit/5b915367da82bd024b2a0d28d2f98007034b4aa2x-refsource-misc
- https://github.com/pypa/virtualenv/releases/tag/21.14.4x-refsource-misc
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.