CVE-2026-113726

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 v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/pypa/virtualenv/commit/5b915367da82bd024b2a0d28d2f98007034b4aa2
https://github.com/pypa/virtualenv/releases/tag/21.14.4
https://github.com/pypa/virtualenv/security/advisories/GHSA-5vjq-rrrf-7h2q

Configurations

No configuration.

History

20 Oct 2026, 22:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-20 22:19

Updated : 2026-10-27 22:17

NVD link : CVE-2026-113726

Mitre link : CVE-2026-113726

CVE.ORG link : CVE-2026-113726

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE-116

Improper Encoding or Escaping of Output

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