# CVE-2026-118905: nvm_ls lets an untrusted version string inject sed commands, executing arbitrary commands with GNU sed


- **Severity:** High 7.1 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 29 Oct 2026
- **Updated:** 29 Oct 2026
- **Also known as:** GHSA-vgqf-vc3m-4wv3

## What is CVE-2026-118905?

CVE-2026-118905 is a high-severity vulnerability in nvm-sh nvm, published on 29 Oct 2026. 

### Official description

Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.31.2 through 0.40.5, `nvm_ls` filters installed versions with a sed program that embeds the requested version pattern in a `\#...#` address, escaping `.` (and, since 0.40.4, `#`) but not backslash. A version string containing `#` (or `\#`) therefore closes the address early, and the rest of it is parsed as sed commands: with GNU sed, the `e` command runs a shell command as the user; with BSD sed, the `w` and `r` commands write and read files. This is reachable whenever an attacker-influenced version string is passed to `nvm use`, `nvm which`, `nvm ls`, `nvm version`, `nvm run`, or `nvm exec`, or to `nvm-exec` via `NODE_VERSION`, and at least one version is installed. nvm's own `.nvmrc` parser strips comments, so a bare `nvm use` is not affected; however, the bash `cdnvm` and zsh `load-nvmrc` auto-switch hooks documented in the README read `.nvmrc` as-is and pass it to `nvm ls` and `nvm version`, so a user with one of those hooks installed runs the attacker's command just by changing into a directory under a malicious `.nvmrc`; scripts that run `nvm use "$(cat .nvmrc)"` are affected the same way. Version 0.40.6 passes any version pattern containing `#` or a newline through the `.nvmrc` content parser first, so no `#` reaches the sed program.

Weakness: CWE-94 (Improper Control of Generation of Code), CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2026-118905?


## How do I fix CVE-2026-118905?

No fix has been published for CVE-2026-118905 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-118905 being exploited?

There is no known exploitation of CVE-2026-118905 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-118905 and fix it if it is affected.

What it is: CVE-2026-118905 is a high-severity vulnerability in nvm-sh nvm, published on 29 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-118905 in the wild and no public exploit code.

Affected product: nvm-sh nvm. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-118905/ (Markdown: https://insights.sbomify.com/CVE-2026-118905/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-118905
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-118905
- OSV: https://osv.dev/vulnerability/CVE-2026-118905

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-118905/
Summaries are generated and may contain mistakes; the official description above is the record.