---
title: "CVE-2026-22686: enclave-vm Vulnerable to Sandbox Escape via Host Error Prototype Chain"
url: https://erroneo.us/security/cve/CVE-2026-22686/
description: "CVE-2026-22686 (enclave-vm (npm)): Enclave is a secure JavaScript sandbox designed for safe AI agent code execution. Prior to 2.7.0, there is a critical…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-01-13
date_modified: 2026-01-15
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-22686"
kev: false
cvss: 10
epss: 0.00753
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-22686: enclave-vm Vulnerable to Sandbox Escape via Host Error Prototype Chain

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.8% , percentile 55: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 55% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes enclave-vm (npm) < 2.7.0, fixed in 2.7.0 . Check your lockfile, including transitive dependencies.

## What it is

Enclave is a secure JavaScript sandbox designed for safe AI agent code execution. Prior to 2.7.0, there is a critical sandbox escape vulnerability in enclave-vm that allows untrusted, sandboxed JavaScript code to execute arbitrary code in the host Node.js runtime. When a tool invocation fails, enclave-vm exposes a host-side Error object to sandboxed code. This Error object retains its host realm prototype chain, which can be traversed to reach the host Function constructor. An attacker can intentionally trigger a host error, then climb the prototype chain. Using the host Function constructor, arbitrary JavaScript can be compiled and executed in the host context, fully bypassing the sandbox and granting access to sensitive resources such as process.env, filesystem, and network. This breaks enclave-vm’s core security guarantee of isolating untrusted code. This vulnerability is fixed in 2.7.0.

## Affected packages

- npm `enclave-vm` < 2.7.0 → fixed: 2.7.0

## Affected products (CVE record)

- agentfront enclave: < 2.7.0

## Severity

- GitHub_M CVSS 3.1: 10 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`
- GitHub CVSS 3.1: 10.0 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.75% probability of exploitation activity in the next 30 days; percentile 55.

## Sources

- [GitHub Advisory GHSA-7qm7-455j-5p63](https://github.com/advisories/GHSA-7qm7-455j-5p63)
- [CVE.org record CVE-2026-22686](https://www.cve.org/CVERecord?id=CVE-2026-22686)
- [NVD entry CVE-2026-22686](https://nvd.nist.gov/vuln/detail/CVE-2026-22686)
- [github.com](https://github.com/agentfront/enclave/security/advisories/GHSA-7qm7-455j-5p63)
- [github.com](https://github.com/agentfront/enclave/commit/ed8bc438b2cd6e6f0b5f2de321e5be6f0169b5a1)

---
Source page: https://erroneo.us/security/cve/CVE-2026-22686/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt