Medium · CVSS 4.5CVE-2026-113716

virtualenv: Builtin creation follows linked environment directoriesCVE-2026-113716

Answer in brief

CVE-2026-113716 records a Medium severity (CVSS 4.5) vulnerability in virtualenv: Builtin creation follows linked environment directories. The current sources do not mark it as known exploited. The current feed maps pypa/virtualenv (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 20, 2026Updated Oct 20, 2026Source checked Oct 20, 2026First seen by HOL Oct 20, 2026Material review Oct 20, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.5
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 4.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps pypa/virtualenv (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
pypa/virtualenvgeneric	<21.14.9	21.14.9

Recommended response

Check inventory. Check lockfiles and deployed manifests for pypa/virtualenv.
Review the reported fix. Update pypa/virtualenv to 21.14.9 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 20, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 20, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 20, 2026

Sources and claim methodology

Upstream source description

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the builtin creator calls ensure_dir() for executable, library, and package directories, and ensure_dir() accepts an existing symlink to a directory because exists() follows it. Interpreter creation, seed installation, and activation generation then write through the linked parent outside the requested destination when another local account prepared the tree and the invoking user can access the target. The --clear option removes the planted tree first, while ordinary creation reaches it; arbitrary attacker-selected output bytes are not established. This issue is fixed in version 21.14.9.

Quoted source text, attributed separately from HOL analysis.