# CVE-2026-43998: vm2: NodeVM require.root bypass via symlink traversal allows sandbox escape

> Attackers can escape the vm2 sandbox via symlink traversal to execute arbitrary code on the host system.

- **Severity:** High 8.5 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 May 2026
- **Updated:** 7 Sep 2026
- **Also known as:** GHSA-cp6g-6699-wx9c, ROOT-APP-NPM-CVE-2026-43998

## What is CVE-2026-43998?

CVE-2026-43998 is a high-severity path traversal vulnerability in patriksimek vm2, published on 13 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

vm2 is an open source vm/sandbox for Node.js. In 3.10.5, NodeVM's require.root path restriction can be bypassed using filesystem symlinks, allowing sandboxed code to load modules from outside the allowed root directory in host context. Because path validation uses path.resolve() (which does not dereference symlinks) but module loading uses Node's native require() (which does), an attacker can load arbitrary host-realm modules and achieve remote code execution. This vulnerability is fixed in 3.11.0.

Weakness: CWE-59 (Improper Link Resolution Before File Access)

## Which versions are affected by CVE-2026-43998?

2 open source packages ship an affected version, including vm2. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `vm2` | npm | From 3.10.5 | 3.11.0 |
| `vm2` | npm | From 3.10.5 | 3.11.0 |

Products: Vm2 Project Vm2.

## How do I fix CVE-2026-43998?

Upgrade vm2 to 3.11.0 or later.

## Is CVE-2026-43998 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43998 exists.

## Other vulnerabilities in patriksimek vm2

- [CVE-2026-43997](https://insights.sbomify.com/CVE-2026-43997/): vm2: Sandbox Escape (critical 10.0)
- [CVE-2026-44005](https://insights.sbomify.com/CVE-2026-44005/): vm2: Sandbox escape (critical 10.0)
- [CVE-2026-44006](https://insights.sbomify.com/CVE-2026-44006/): vm2: Sandbox Escape (critical 10.0)
- [CVE-2023-29017](https://insights.sbomify.com/CVE-2023-29017/): vm2 Sandbox Escape vulnerability (critical 10.0)
- [CVE-2022-36067](https://insights.sbomify.com/CVE-2022-36067/): vm2 vulnerable to Sandbox Escape before v3.9.11 (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-43998 and fix it if it is affected.

What it is: CVE-2026-43998 is a high-severity path traversal vulnerability in patriksimek vm2, published on 13 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43998 exists.

Affected packages and fixed versions:
- vm2 (npm): affected from 3.10.5; fixed in 3.11.0
- vm2 (npm): affected from 3.10.5; fixed in 3.11.0

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-2026-43998/ (Markdown: https://insights.sbomify.com/CVE-2026-43998/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-43998
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-43998
- OSV: https://osv.dev/vulnerability/CVE-2026-43998

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-43998/
Summaries are generated and may contain mistakes; the official description above is the record.