Pyenv provides simple Python version management. Prior to 2.8.0, is_version_safe() in libexec/pyenv-version-file-read accepts shell glob metacharacters in .python-version values, and unquoted PYENV_VERSION expansion in libexec/pyenv-version-name, libexec/pyenv-which, libexec/pyenv-prefix, libexec/pyenv-local, libexec/pyenv-global, libexec/pyenv-version, and libexec/pyenv-versions pathname-expands the value against the current directory, allowing a matching attacker-controlled file to silently select a different installed interpreter or version. This issue is fixed in version 2.8.0.