CVE-2026-113720

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the app-data copy seeder uses shutil.copy() to copy cached package files into later environments, causing cached source modes to override the current run's umask. A cache populated under a permissive umask can therefore produce files writable by another local account in a later traversable environment, allowing package code such as pip/__init__.py to be modified and executed by the environment owner. The attacker cannot force the earlier umask, and a private destination parent prevents access. This issue is fixed in version 21.14.9.

CVSS 4.0

4.4CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N

EPSS

0.1% chance of exploitation in the next 30 days; higher than 2% of CVEs (scores of 2026-10-25)

CWE

CWE-732

Published

2026-10-20

Modified

2026-10-22

Record from

the NVD, synced 2026-10-23

Packages (OSV)

References

• https://github.com/pypa/virtualenv/commit/35f0b33562790176dd186d0a3c517af3acc7a0e1
• https://github.com/pypa/virtualenv/pull/3425
• https://github.com/pypa/virtualenv/releases/tag/21.14.9
• https://github.com/pypa/virtualenv/security/advisories/GHSA-fc2g-4w5p-6whm

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