CRLF Injection Affecting virtualenv package, versions [,21.7.11)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-VIRTUALENV-20335493
- published30 Sept 2026
- disclosed29 Sept 2026
- creditBernát Gábor
Introduced: 29 Sep 2026
NewCVE-2026-102938 (opens in a new tab)How to fix?
Upgrade virtualenv to version 21.7.11 or higher.
Overview
Affected versions of this package are vulnerable to CRLF Injection via the PyEnvCfg.write method in src/virtualenv/create/pyenv_cfg.py, where configuration values containing line boundary characters (such as \n, \r, \v, \f, and Unicode line/paragraph separators) are written into pyvenv.cfg without sanitization. An attacker who controls a value written to pyvenv.cfg - for example, the virtual environment prompt - can inject additional configuration keys into the file, which are then read back as legitimate entries and can override critical settings such as home.