virtualenv is a tool for creating isolated virtual python environments. Prior to version 20.36.1, TOCTOU (Time-of-Check-Time-of-Use) vulnerabilities in virtualenv allow local attackers to perform symlink-based attacks on directory creation operations. An attacker with local access can exploit a race condition between directory existence checks and creation to redirect virtualenv's app_data and lock file operations to attacker-controlled locations. This issue has been patched in version 20.36.1.
https://github.com/pypa/virtualenv/security/advisories/GHSA-597g-3phw-6986
https://github.com/pypa/virtualenv/pull/3013
https://github.com/pypa/virtualenv/commit/dec4cec5d16edaf83a00a658f32d1e032661cebc