https://db.gcve.eu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Thu, 22 Oct 2026 17:45:58 +0000 https://db.gcve.eu/vuln/fkie_cve-2026-113721 <p>virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, ViaTemplateActivator._generate() removes an existing output only when Path.exists() is true, allowing a dangling symlink to survive and redirect generated activation content, while PyEnvCfg.write() opens pyvenv.cfg without first replacing an existing symbolic or hard link. Another local account that prepares final entries inside the destination can therefore cause environment creation to create or overwrite files outside the requested tree with constrained virtualenv-generated content and the invoking user&#39;s permissions. The destination parent must remain controlled by the environment owner during creation; concurrent parent-directory replacement is a separate concern. This issue is fixed in version 21.14.9.</p> <p>virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, ViaTemplateActivator._generate() removes an existing output only when Path.exists() is true, allowing a dangling symlink to survive and redirect generated activation content, while PyEnvCfg.write() opens pyvenv.cfg without first replacing an existing symbolic or hard link. Another local account that prepares final entries inside the destination can therefore cause environment creation to create or overwrite files outside the requested tree with constrained virtualenv-generated content and the invoking user&#39;s permissions. The destination parent must remain controlled by the environment owner during creation; concurrent parent-directory replacement is a separate concern. This issue is fixed in version 21.14.9.</p> https://db.gcve.eu/vuln/fkie_cve-2026-113721 https://db.gcve.eu/vuln/ghsa-558c-9hv2-4prj <p><strong>Affected:</strong> PyPI: virtualenv</p> <p>## Summary</p> <p>Generated activation files and pyvenv.cfg can follow existing links and write outside the requested environment. The template writer tests exists() before unlinking, which misses dangling symlinks; the configuration writer opens the existing path directly.</p> <p>Anthropic&#39;s OSS Scanner reported this as `ANT-2026-XBEOCBS1` in `virtualenv-20261015-005`, received on 15 October 2026.</p> <p>## Affected area</p> <p>Final file entries written during environment creation and seeding.</p> <p>## Attacker-controlled input</p> <p>Another account must be able to prepare file links in the destination before creation. The invoking user must have write permission at the linked target. The destination parent must remain controlled during creation; concurrent parent-directory replacement is a separate concern.</p> <p>## Affected code</p> <p>The relevant 21.14.8 source is in [template writer](https://github.com/pypa/virtualenv/blob/a795ab116356afde11039cf2763d77e8a06da738/src/virtualenv/activation/via_template.py), [configuration writer](https://github.com/pypa/virtualenv/blob/a795ab116356afde11039cf2763d77e8a06da738/src/virtualenv/create/pyenv_cfg.py).</p> <p>## Mechanism</p> <p>`ViaTemplateActivator._generate()` removes an existing output only when `Path.exists()` is true. A dangling symlink therefore survives, and `write_bytes()` creates its target outside the environment. Other generated files have related final-entry behavior. `PyEnvCfg.write()` opens `pyvenv.cfg` without first replacing an existing link; a symlink or hard link…</p> <p><strong>Affected:</strong> PyPI: virtualenv</p> <p>## Summary</p> <p>Generated activation files and pyvenv.cfg can follow existing links and write outside the requested environment. The template writer tests exists() before unlinking, which misses dangling symlinks; the configuration writer opens the existing path directly.</p> <p>Anthropic&#39;s OSS Scanner reported this as `ANT-2026-XBEOCBS1` in `virtualenv-20261015-005`, received on 15 October 2026.</p> <p>## Affected area</p> <p>Final file entries written during environment creation and seeding.</p> <p>## Attacker-controlled input</p> <p>Another account must be able to prepare file links in the destination before creation. The invoking user must have write permission at the linked target. The destination parent must remain controlled during creation; concurrent parent-directory replacement is a separate concern.</p> <p>## Affected code</p> <p>The relevant 21.14.8 source is in [template writer](https://github.com/pypa/virtualenv/blob/a795ab116356afde11039cf2763d77e8a06da738/src/virtualenv/activation/via_template.py), [configuration writer](https://github.com/pypa/virtualenv/blob/a795ab116356afde11039cf2763d77e8a06da738/src/virtualenv/create/pyenv_cfg.py).</p> <p>## Mechanism</p> <p>`ViaTemplateActivator._generate()` removes an existing output only when `Path.exists()` is true. A dangling symlink therefore survives, and `write_bytes()` creates its target outside the environment. Other generated files have related final-entry behavior. `PyEnvCfg.write()` opens `pyvenv.cfg` without first replacing an existing link; a symlink or hard link…</p> https://db.gcve.eu/vuln/ghsa-558c-9hv2-4prj