nodejs / nodejs/node

FATAL ERROR: v8::ToLocalChecked Empty MaybeLocal

Open
#56,531 18 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

c++ child_process good first issue
Dominant language
JavaScript
Stars
122k
Forks
37.3k
Avg merge
4d 2h
Merged PRs (30d)
283

Description

Version

v23.6.0

Platform
Linux SMP Debian 5.10.103-1 (2022-03-07) x86_64 x86_64 x86_64 GNU/Linux
Subsystem

No response

What steps will reproduce the bug?

Hi,

I would like to report a bug, it can be reproduced by running the PoC below:

const {exec} = require('child_process');

Object.defineProperty(Array.prototype, "2", {
  set: function () {},
});

(async function () {
  exec('pwd', (err, stdout, stderr) => {
    console.log(stdout);
  });
})();

Regards,

AH

How often does it reproduce? Is there a required condition?

It reproduces anytime by simply running the given PoC on the given Node.js version.

What is the expected behavior? Why is that the expected behavior?

It is a crash.

What do you see instead?

FATAL ERROR: v8::ToLocalChecked Empty MaybeLocal

Additional information

No response

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by running the JavaScript PoC with child_process.exec on Node.js v23.6.0 and confirm the fatal error. Trace the child_process exec path involved in the crash; done means the reproduction no longer terminates with “v8::ToLocalChecked Empty MaybeLocal” and a regression test covers the PoC.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript, nodejs
Domain
backend
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Active
Clarity
Mostly clear
Newbie friendliness
48/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.