CVE-2026-15921
LowCVSS 3.1Exploitation Probability (EPSS)
Low risk13th percentile - higher than 13% of all known CVEs
Summary
Node Version Manager (nvm) versions 0.32.1 through 0.40.5 are vulnerable to path traversal when parsing LTS codenames from a mirror. A malicious mirror can inject path sequences like "../../../.bashrc", causing nvm to write version strings outside the intended alias directory, potentially overwriting shell startup files.
Risk Assessment
An attacker can achieve code execution in a victim's shell session by overwriting startup files (e.g., .bashrc) via a compromised mirror or MITM attack. This poses a critical risk in environments using untrusted mirrors or insecure connections.
Recommendation
Upgrade nvm to version 0.40.6 or later immediately. Ensure mirrors are trusted and connections use HTTPS to prevent MITM attacks.
Original NVD description (English source)
Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.32.1 through 0.40.5, `nvm ls-remote` (and other commands that refresh remote LTS aliases, such as `nvm install --lts`) parse the node.js mirror's `index.tab` and use each release's LTS codename field as an alias filename without validating it. A malicious, compromised, or man-in-the-middled mirror can return an LTS codename containing path-traversal sequences such as `../../../.bashrc`, causing nvm to write the associated version string to a path outside `$NVM_DIR/alias`. With the default layout (`$NVM_DIR` is `~/.nvm`), this can create or overwrite files in the user's home directory, including shell startup files, which can lead to code execution in a later shell session. Exploitation requires the victim to use a hostile mirror -- via a compromised mirror or CDN, a network man-in-the-middle, or a maliciously configured `NVM_NODEJS_ORG_MIRROR`/`NVM_IOJS_ORG_MIRROR` -- and to run an affected command. Version 0.40.6 validates remote LTS codenames as safe alias filenames and rejects `..` path components when writing alias files.