CVE-2026-113715

virtualenv: Venv configuration readback can reinterpret path boundaries

Published Oct 20, 2026 CVSS 4.0 · 2 Low EPSS < 1% KEV · Not listed
Description
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the stdlib venv creator reads generated pyvenv.cfg with str.splitlines() and merges parsed keys over virtualenv's selected configuration. An untrusted caller who influences the destination pathname can include a line-boundary character such as U+2028 to inject keys including home and include-system-site-packages, causing path data to change configuration structure before final output. Setting include-system-site-packages to true weakens environment isolation, while an altered home can change which standard-library files the interpreter loads if the attacker also controls that location. The builtin creator does not use this readback path. This issue is fixed in version 21.14.9.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-qmx5-4p3x-wvqf virtualenv: Venv configuration readback can reinterpret path boundaries
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 4.5, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L'}

threat_severity

Moderate

Type Values Removed Values Added
First Time appeared Pypa
Pypa virtualenv
Vendors & Products Pypa
Pypa virtualenv
Type Values Removed Values Added
Description virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the stdlib venv creator reads generated pyvenv.cfg with str.splitlines() and merges parsed keys over virtualenv's selected configuration. An untrusted caller who influences the destination pathname can include a line-boundary character such as U+2028 to inject keys including home and include-system-site-packages, causing path data to change configuration structure before final output. Setting include-system-site-packages to true weakens environment isolation, while an altered home can change which standard-library files the interpreter loads if the attacker also controls that location. The builtin creator does not use this readback path. This issue is fixed in version 21.14.9.
Title virtualenv: Venv configuration readback can reinterpret path boundaries
Weaknesses CWE-93
References
Metrics cvssV4_0

{'score': 2, 'vector': 'CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 23, 2026, 2:01 AM
Reserved
Oct 20, 2026, 4:03 PM
Status
Awaiting Analysis
Published
Oct 20, 2026, 8:17 PM
Modified
Oct 23, 2026, 2:16 AM
Severity
Moderate
Public date
Oct 20, 2026, 7:42 PM