A command injection issue exists in nvm (Node Version Manager). The `nvm download()` function utilizes `eval` to execute `wget` commands. The `NVM AUTH HEADER` environment variable was not properly sanitized when used in the `wget` code path. An attacker capable of setting environment variables within a victim’s shell environment—for example, through malicious CI/CD configurations, compromised dotfiles, or Docker images—can inject arbitrary shell commands. These commands will execute when the victim runs nvm commands that initiate downloads, such as 'nvm install' or 'nvm ls-remote'.