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.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 21 Oct 2026 00:30:00 +0000

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


Tue, 20 Oct 2026 21:00:00 +0000

Type Values Removed Values Added
First Time appeared Pypa
Pypa virtualenv
Vendors & Products Pypa
Pypa virtualenv

Tue, 20 Oct 2026 19:45:00 +0000

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'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-10-20T19:42:55.011Z

Reserved: 2026-10-20T16:03:14.862Z

Link: CVE-2026-113715

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-20T20:17:17.690

Modified: 2026-10-20T20:17:17.690

Link: CVE-2026-113715

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-20T19:42:55Z

Links: CVE-2026-113715 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-10-20T20:45:14Z

Weaknesses