---
id: "CVE-2026-121748"
kind: "vulnerability"
aliases: ["CVE-2026-121748"]
title: "nvm: project .npmrc can make --delete-prefix corrupt or expose a config file"
severity: "low"
cvss: 3.6
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["developer-workstations", "node", "nvm", "package", "shell"]
not_affected_if: ["no-npmrc-prefix", "nvm-0.41.0-or-later", "nvm-below-0.27.0", "single-user-machine"]
published_at: "2026-11-04T22:17:54+00:00"
first_seen_at: "2026-11-04T23:08:47+00:00"
updated_at: "2026-11-04T23:10:09+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121748", "first_seen_at": "2026-11-04T23:08:47+00:00"}]
exploit_sources: []
---

# nvm: project .npmrc can make --delete-prefix corrupt or expose a config file

nvm's `nvm use --delete-prefix` runs npm config deletes in the current directory without naming a config file, so a project's `.npmrc` can pick which file gets rewritten. An attacker who writes a cloned repository or shared directory can corrupt a file such as `~/.bashrc` or leave a global config writable by other local users.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the nvm version with `nvm --version` or the installed nvm script version; versions `0.27.0` through `0.40.8` are affected.
- Look for a `prefix` setting in project `.npmrc` files you use with `nvm use`.

## Fix

- Move nvm to `0.41.0` or later, which no longer lets a project `.npmrc` select the file `--delete-prefix` edits.

## Timeline

- 2026-11-04T23:08:47+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121748

## Documents

- [advisory] Vendor advisory: github.com https://github.com/nvm-sh/nvm/security/advisories/GHSA-ccgf-7gv4-xg5h
- [fix] Patch: github.com https://github.com/nvm-sh/nvm/commit/4049296ca8eef2067517d8cfd5ef5c0e615daa10

## From the sources

Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.27.0 through 0.40.8, when a project's `.npmrc` sets `prefix`, `nvm use` tells the user to run `nvm use --delete-prefix`, which runs `npm config delete prefix` and `npm config delete globalconfig` in the current directory without naming a config file. npm loads the project `.npmrc` before deciding which file to edit, so that file chooses the target: `userconfig=~/.bashrc` makes npm rewrite `~/.bashrc` as ini (corrupting it), and `location=global` with `globalconfig=` leaves the chosen file at mode 0666, which on a shared machine lets another local user write to it. The attacker (the author of a cloned repository or archive, or a local user who can write a shared parent directory) chooses the file but not the bytes written, and no project code runs. Version 0.41.0 no longer lets a project `.npmrc` select which config file `--delete-prefix` edits.

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