virtualenv, a tool for creating isolated Python environments, allows the seeding process to join entries from legacy metadata files without validating containment. When an attacker can influence the seed-package metadata or supply files with relative traversal, absolute paths, or symlinked parents, the seeding routine may delete files outside the virtual environment root or even the environment root itself. This deletion occurs during environment creation, before any use of the environment, and can result in loss of critical files or denial of functionality. The weakness is a path traversal issue identified as CWE‑22.

The vulnerability exists in all versions of pypa:virtualenv released before 21.14.9. The issue is triggered when PipInstall._uninstall_previous_version() processes existing seed‑package metadata, so any prior release that does not include the patch is affected.

The CVSS score is 4.5, indicating a moderate severity. EPSS is not available, but the vulnerability is not listed in CISA KEV. The likely attack vector is a privileged or delegated user who can supply or manipulate seed‑package metadata. Because the deletion occurs during environment creation, exploitation only requires the user to have deletion rights over the target paths. Once enabled, the attacker can remove arbitrary files on the system, potentially compromising system integrity and availability.