CVE-2026-113722: virtualenv: Generated POSIX console launchers interpret destination paths as shell syntax

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-20 · updated 2026-10-23
Weakness: CWE-78

Description

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, virtualenv's ScriptMakerCustom and pip pass an incompletely quoted interpreter path to distlib ScriptMaker when generating POSIX console scripts. When the path contains a space or produces a shebang longer than 127 bytes, distlib emits a /bin/sh wrapper whose double-quoted interpreter path still expands command substitutions and backticks. An attacker who influences the environment destination can therefore execute commands with the user's privileges when the user later runs a generated launcher; environment creation and activation do not trigger the command. Existing launchers are not repaired by upgrading virtualenv alone and must be regenerated, while a later independent pip installation or upgrade can reintroduce an affected launcher because pip's vendored distlib is unchanged. The virtualenv fix is released in version 21.14.9.

Affected products

Pypi Virtualenv: before 21.14.9; 0.8, 0.8.1, 0.8.2, 0.8.3, 0.8.4, 0.9 (+298) — fixed in 21.14.9
pypa virtualenv: before 21.14.9

How to fix

Upgrade to a fixed version: Pypi Virtualenv 21.14.9. Check the vendor advisory for mitigations.

References

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