Threats affecting pkg:github/nvm-sh/nvm

nvm (Node Version Manager) through 0.40.4 executes arbitrary commands from version strings supplied by the configured Node.js/io.js mirror. Commands such as `nvm install` read the available versions from the mirror's index.tab and use the selected version, without sanitization, to build download URLs and shell/awk commands. Two sinks are affected by the same untrusted input: nvm_download() built a curl/wget command string and ran it with `eval`, so a version field containing command substitution (for example $(id)) was executed by the local shell; and nvm_get_checksum() interpolated the version-derived download slug into an awk program, so a crafted version could execute arbitrary commands via awk's system(). An attacker who controls the configured mirror, supplies mirror content to a user or CI on a non-default mirror, or machine-in-the-middles a non-TLS mirror can ∴ run arbitrary commands with the privileges of the user running nvm. The default mirror (https://nodejs.org over TLS) is not affected. Fixed on master (pending the next tagged release) by passing every argument as a literal argv element instead of using eval, by passing the value to awk as data via -v instead of interpolating it into the program, and by rejecting any version outside the Node.js/io.js version grammar before it is used.

CVE-2026-1665 is a command injection vulnerability in nvm (Node Version Manager) versions 0.40.3 and below. The vulnerability arises because the nvm_download() function uses eval to execute wget commands without properly sanitizing the NVM_AUTH_HEADER environment variable. An attacker who can control environment variables in a victim’s shell environment—such as through malicious CI/CD configurations, compromised dotfiles, or Docker images—can inject arbitrary shell commands. These commands execute when the victim runs nvm commands that trigger downloads, like 'nvm install' or 'nvm ls-remote'. The CVSS 4.0 score is 5.4 (medium severity), reflecting the need for local privileges and user interaction. There are no known exploits in the wild yet.